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PD6908 Ex-Proof & I.S. Loop-Powered Process Meter
Instruction Manual
PRECISION DIGITAL CORPORATION
233 South Street • Hopkinton MA 01748 USA
Tel (800) 343-1001 • Fax (508) 655-8990
www.predig.com
• Fully-Approved Explosion-Proof & Intrinsically Safe Loop-Powered Process Meters
• 4-20 mA Input Displayed with ±0.02% of Full-Scale Accuracy
• 1.5 Volt Drop (4.7 Volt Drop with Backlight)
• 0.7" (17.0 mm) 5 Alphanumeric Characters Top Display
• 0.4" (10.2 mm) 8 Alphanumeric Characters Bottom Display
• 20-Segment Bargraph Standard
• Display Mountable at 0°, 90°, 180°, & 270°
• CapTouch Through-Glass Button Programming with Normal and Delayed Modes
• Loop-Powered Backlight with Red Backlight for Alarm Conditions
• (2) Open Collector Outputs Standard; Assignable to Pulse, Alarm, Timer, or Stopwatch
• (2) Optional Loop-Powered Solid-State Relays; Assignable to Alarm, Control, Timer, or Stopwatch
• Stopwatch & Timer Functions to Drive Relays & Open Collectors
• Optional Isolated 4-20 mA Analog Output
• Relay Pump Alternation Based on Level and Runtime
• Display Relay Runtime & Cycle Count via Relay Info Menu
• Round Horizontal Tank Function; Just Enter Diameter & Length
• 32-Point Linearization, Square Root Extraction and Programmable Exponent Function
• Free PC-Based MeterView XL USB Programming Software
• HART® Protocol Transparent
• Enable and Disable Backlight from Menu
• Operating Temperature Range: -40 to 75°C (-40 to 167°F)
• Installation Temperature Range: -55 to 75°C (-67 to 167°F)
• Conformal Coated PCBs for Dust & Humidity Protection
• Password Protection
• CSA Certified for Explosion-Proof / Dust-Ignition Proof / Flame-Proof
• ATEX and IECEx Certified as Intrinsically Safe
• Flange for Wall or Pipe Mounting; Loop for Stainless Steel Tag; Holes for Tamper-Proof Seal
• Explosion-Proof, IP68, NEMA 4X Die-Cast Aluminum & Stainless Steel Enclosures
• 3-Year Warranty
IECEx
MeterView XL
USB Install
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Instruction Manual
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The Complete PD6900 Series
Plastic Enclosures - General Purpose
PD6907-GP-PL
Feet & Inches Meter
PD6908-GP-PL
Process Meter
PD6928-GP-PL
Flow Rate/Totalizer
Aluminum Enclosures - Explosion-Proof & I.S.
PD6907-HA-AL
Feet & Inches Meter
PD6908-HA-AL
Process Meter
PD6928-HA-AL
Flow Rate/Totalizer
Stainless Steel Enclosures - Explosion-Proof & I.S.
PD6907-HA-SS
Feet & Inches Meter
PD6908-HA-SS
Process Meter
PD6928-HA-SS
Flow Rate/Totalizer
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Instruction Manual
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Table of Contents
Introduction .......................................................................................................... 6
Key Features ........................................................................................................ 7
Ordering Information ......................................................................................... 11
Accessories ................................................................................................... 11
Specifications..................................................................................................... 13
Display ............................................................................................................ 13
General ........................................................................................................... 13
Enclosure ....................................................................................................... 14
Input ................................................................................................................ 14
Common Open Collector & Relay Specifications ....................................... 15
Open Collector Outputs ................................................................................ 15
Solid-State Relays ......................................................................................... 15
4-20 mA Transmitter Output ......................................................................... 15
On-Board Digital Input .................................................................................. 15
MeterView XL Software ................................................................................. 16
Compliance Information .................................................................................... 17
Hazardous Area Approvals ........................................................................... 17
Electromagnetic Compatibility ..................................................................... 17
EU Declaration of Conformity ........................................................................... 18
Safety Information ............................................................................................. 18
Installation .......................................................................................................... 18
Unpacking ...................................................................................................... 18
Mounting ............................................................................................................. 19
Dimensions .................................................................................................... 19
Cover Jam Screw ........................................................................................... 19
Connections ....................................................................................................... 20
Display & Options Modules .......................................................................... 20
Connectors Labeling ..................................................................................... 21
Wiring Diagrams ................................................................................................ 23
Intrinsically Safe Wiring ................................................................................ 23
I/O Parameter Table .................................................................................... 23
Explosion-Proof Wiring ................................................................................. 23
Current Loop (4-20 mA) Connections ......................................................... 23
Digital Input Connections ............................................................................ 24
4-20 mA Output Connections ...................................................................... 24
Solid-State Relay Connections.................................................................... 24
Open Collector Output Connections............................................................ 24
Setup and Programming ................................................................................... 25
Overview ......................................................................................................... 25
CapTouch Buttons ........................................................................................ 25
CapTouch Buttons Delay ............................................................................ 25
Disabling the CapTouch Buttons ................................................................. 25
CapTouch Button Tips & Troubleshooting .................................................. 25
MeterView XL Programming Software ......................................................... 26
CapTouch Buttons and Status Indicators ................................................... 27
Display Functions & Messages .................................................................... 28
Main Menu ...................................................................................................... 32
Setting Numeric Values ............................................................................... 33
Scaling the 4-20 mA Input (INPUT) ................................................................... 34
Available Unit Classes and Units ................................................................ 35
Setting Custom Units (CUSTOM) .................................................................. 36
Setting the Display Features (DISPLAY) ..................................................... 36
Changing the Engineering Units (UNITS) ................................................... 36
Changing the Decimal Point (DEC.PT) ......................................................... 36
Enabling or Disabling Commas on the Bottom Display (COMMA) ................ 37
Display Capabilities Optimization (TOP and BOTTOM) ................................ 37
Configuring the Display (TOp and BOTTOM) ................................................ 38
Programming the Bargraph (BARGRAPH) .................................................... 39
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Programming the Outputs (OUTPUT) ........................................................... 39
Open Collector Outputs
(
OPEN COLLECTR
)
................................................. 40
Solid-State Relay Outputs (RELAY) ............................................................ 45
Isolated 4-20 mA Output (4-20 mA) .......................................................... 51
Output Manual Control (CONTROL) ............................................................. 51
Advanced Features Menu (ADVANCE) .......................................................... 52
Advanced Process Variable Setup (ADV PV SETUP) ............................... 53
Low-Flow Cutoff (CUTOFF).......................................................................... 60
Noise Filter (FILTER) ................................................................................. 60
Enabling Password Protection (PASSWRD) ................................................. 60
Programmable Function Keys User Menu (USER) ...................................... 61
Tare (TARE) ................................................................................................. 62
Changing System Settings (SYSTEM) ......................................................... 63
Meter Operation ................................................................................................. 65
CapTouch Buttons Operation ...................................................................... 65
CapTouch Buttons ........................................................................................ 65
CapTouch Button Tips & Troubleshooting .................................................. 65
Function Keys Operation .............................................................................. 66
Digital Input Operation .................................................................................. 66
Maximum/Minimum Readings ...................................................................... 66
Runtime & Cycle Count (INFO) .................................................................... 66
Changing Engineering Units ........................................................................ 66
Troubleshooting................................................................................................. 67
Reset Meter to Factory Defaults ................................................................... 67
Determining Software Version ..................................................................... 67
Factory Default Settings .............................................................................. 68
Troubleshooting Tips .................................................................................... 69
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Table of Figures
Figure 1. Enclosure Dimensions – Front View .................................................... 19
Figure 2. Enclosure Dimensions – Side View ..................................................... 19
Figure 3. Enclosure Dimensions – Top View ...................................................... 19
Figure 4. Connector Labeling for PD6908-HA-##-LNN ....................................... 21
Figure 5. Connector Labeling for PD6908-HA-##-L2N ........................................ 21
Figure 6. Connector Labeling for PD6908-HA-##-L3N ........................................ 22
Figure 7. Connector Labeling for PD6908-HA-##-L5N ........................................ 22
Figure 8. 4-20 mA Input Connection without Backlight ..................................... 23
Figure 9. 4-20 mA Input Connection with Backlight ........................................... 23
Figure 10. Digital Input Connections ................................................................... 24
Figure 11. 4-20 mA Output Connections ............................................................. 24
Figure 12. Solid-State Relay Connections ........................................................... 24
Figure 13. Open Collector Output Connections.................................................. 24
Video
Watch the Loop-Powered Meters Video
Click or Scan
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Instruction Manual
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Disclaimer
The information contained in this document is
subject to change without notice. Precision Digital
Corporation makes no representations or
warranties with respect to the contents hereof;
and specifically disclaims any implied warranties
of merchantability or fitness for a particular
purpose.
• Read complete instructions prior to installation
and operation of the meter.
• This product is not recommended for life support
applications or applications where malfunctioning
could result in personal injury or property loss.
Anyone using this product for such applications
does so at his/her own risk. Precision Digital
Corporation shall not be held liable for damages
resulting from such improper use.
• Failure to follow installation guidelines could
result in death or serious injury. Make sure only
qualified personnel perform the installation.
• For Explosion-Proof / Dust-Ignition Proof / Flame-
Proof applications, never remove the meter cover
in explosive environments when the circuit is live.
• Cover must be fully engaged to meet for
Explosion-Proof / Dust-Ignition Proof / FlameProof requirements.
WARNING
Cancer and Reproductive Harm - www.P65Warnings.ca.gov
Limited Warranty
Precision Digital Corporation warrants this
product against defects in material or
workmanship for the specified period under
“Specifications” from the date of shipment from
the factory. Precision Digital’s liability under this
limited warranty shall not exceed the purchase
value, repair, or replacement of the defective unit.
See Warranty Information and Terms &
Conditions on www.predig.com for complete
details.
Registered Trademarks
All trademarks mentioned in this document are
the property of their respective owners.
© 2022 Precision Digital Corporation.
All rights reserved.
Introduction
The PD6908 ProtEX+ loop-powered explosion-proof
& intrinsically safe meters can be installed virtually
anywhere to provide convenient and informative
display of any 4-20 mA signal. They can operate
down to -40°C and be installed in areas that get as
cold as -55°C, however the display will cease
functioning. One of the most convenient features of
these instruments is their dual-line display which is
typically used to display the process variable on the
5-character alphanumeric top display and the units of
measure or a tag on the 8-character alphanumeric
bottom display. Another common setup is to display
the input in one scale on the top display (such as feet)
and in another scale on the bottom display (such as
gallons). The top display uses 12-segment, and the
bottom display uses 14-segment alphanumeric
characters for clear indication of tags, units, or alarm
messages.
Further enhancing the display on these instruments is
a 20-segment bargraph.
These loop-powered meters can be installed virtually
anywhere because they get their power from the
4-20 mA loop and therefore require no separate
power source. And they only drop 1.5 V (4.7 V with
backlight), so they add very little burden to the loop.
Additional features that allow these instruments to be
installed virtually anywhere include a NEMA 4X, IP68
explosion-proof enclosure, an operating temperature
range of -40 to 167°F (-40 to 75°C), conformally
coated PCBs, and a backlit LCD that can be read in
bright sunlight or dimly lit areas.
The ProtEX+ Series is CSA Certified as ExplosionProof / Dust-Ignition Proof / Flame-Proof and ATEX
and IECEx Certified as Intrinsically Safe. The
enclosure itself is ATEX, IECEx, CSA, and UL
approved.
Free, PC-based, MeterView XL software that
connects to the meter via a micro USB cable is
available for programming and setup of the meters.
For more details, see the MeterView XL manual. Four
CapTouch through-glass buttons are available to
operate the instrument without removing the cover.
All models come equipped with two open collector
outputs and a digital input. There are also models
available with two solid-state relays and isolated
4-20 mA analog output options. The open collector
outputs are useful for alarm indication. The digital
input can be used to acknowledge the relays, to
start/stop a timer/stopwatch, and more. The relays
can be programmed for alarm indication, on/off
control, or pump alternation.
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Key Features
2X More Informative Display
The PD6908 display offers a 50% larger display area
and is twice more informative than previous
generations of loop-powered explosion-proof meters.
Featuring an alphanumeric dual-line display and a
20-segment bargraph, reading and understanding
process values is easy and intuitive. The addition of
status indicators provides a quick glance at alarm
conditions, relays, process trends, and more.
Predefined display units give users even more display
flexibility. Plus, the high contrast backlit LCD display
is readable from far away and under various lighting
conditions.
Backlight Turns Red on Alarm
When an alarm occurs, the display can be
programmed to turn red, flash, and display an alarm
indicator . In addition, a unique custom alarm
message for each of the two relays and two open
collectors can be displayed on the bottom display.
These features can be activated even if no relay or
open collector is connected.
CapTouch Through-Glass
Buttons
The PD6908 is equipped with four capacitive sensors
that operate as through-glass buttons so that it can be
operated without removing the cover (and exposing
the electronics) in a hazardous area. CapTouch
buttons are designed to work under any lighting
condition and to protect against false triggering. They
can be disabled for security via a switch on the
display module.
CapTouch buttons have two modes of operation:
Normal and Delayed. Delayed mode prevents
accidental trigger of the buttons. In the Delayed
mode, the buttons enter into a low sensitivity state
(sleep) and they ignore quick button presses after 20
seconds of inactivity. To wake up the buttons, press
and hold any button for more than 2 seconds, the
buttons respond normally.
Solid State Relays 1-2
Indicators
Predefined
Display Units
0.7" (17.0 mm) High
5-Character, Alphanumeric
12-segment
Password Protection
Process Trend
Indicators
CapTouch Buttons
Self-Calibration
0.4" (10.2 mm) High
8-Character, Alphanumeric
14-segment
Two-Color
Backlight
Alarm Indicator
20-Segment
Bargraph
CapTouch Buttons /
Function Keys
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Wide Viewing Angle
The window and display module have been optimized
to provide a wide viewing angle of approximately
±40°; nearly twice that of the competition. Plus, the
display module can be rotated in 90° increments
providing added mounting flexibility.
Dual-Scale Feature
Users can use the dual-scale feature to display the
input in two different scales. For instance, the
example above shows an application where the
display shows the input in feet and gallons while the
display toggles between process values and units.
Predefined and Custom Units
The meter has six available preprogrammed unit
classes: volume, height, temperature, pressure,
weight, and rate. When the desired unit class or unit
of measure within a class is not available, a custom
unit may be programmed.
14-Segment Characters
Notice how much better letters like “T”, “N” and “K”
appear as 14-segment characters on the bottom display
vs. 7-segment characters found on other meters.
Password Protection
A password can be set up for programming security to
prevent unauthorized changes to the programmed
parameter settings.
Enable / Disable Backlight
The backlight may be enabled or disabled using the
System - Backlight menu. The backlight is enabled by
default, but the input must be wired appropriately for
the backlight to function. See Enabling or Disabling
the Backlight (BACKLITE) on page 64 for details.
Multiple Outputs
• Two open collector outputs (standard)
• Two solid-state relays (optional)
• One 4-20 mA output (optional)
The open collector outputs and relays generally
operate in the same manner, with the major exception
being the open collectors are not available for pump
alternation and the relays are not available with pulse
features. The open collectors and relays can be
controlled either automatically or manually.
The isolated analog output signal can be configured
to represent the process variable (PV1, PV2, or
retransmit). It can also be reverse scaled such that
the meter’s high calibration value outputs 4 mA and
the meter’s low calibration outputs 20 mA.
Free MeterView XL
Programming Software
The fastest and easiest way to program the meter is
using the free Meterview XL programming software.
This software greatly simplifies the programming
process and allows the user to save configuration files
for later use.
The meter connects to the PC via a provided microUSB cable and is powered by the USB connection, so
no additional power is needed during programming.
Easy Wiring & Service
The PD6908 has been designed for easy wiring and
servicing. All connections are made to removable
screw terminal blocks. There are no exposed printed
circuit boards.
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Modern and Practical Enclosure
The PD6908 NEMA 4X, IP68 enclosure provides
serious protection from the elements, high impact,
corrosion, and electrical interference. Plus, the
extensive worldwide agency approvals allow it to be
installed virtually anywhere.
Aluminum or Stainless Steel Enclosure
The enclosure is available in copper-free (0.3%),
die-cast aluminum and type 316 stainless steel.
Built-In Flange for Pipe Mounting
The built-in mounting flange allows easy mounting to
walls or pipes.
A slot on the back makes it easy to center the unit on
a pipe. There are two ¾" NPT threaded conduit holes
for wiring.
Grounding Screw
A grounding screw is provided on the top of the
enclosure.
SS Tag Attaching Loop
The enclosure is also equipped with a loop at the top
to easily attach a PDA-SSTAG stainless steel tag.
Tamper-Proof Capability
The instrument can be made tamper-proof by
inserting a wire through the built-in loop on the base
of the enclosure and a hole in the lid of the enclosure
and securing this wire with a lead seal.
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Pump Alternation
The PD6908 can be used as a pump controller to
alternate two pumps and indicate high and low alarm
conditions. The pumps can be programmed to
alternate on level and runtime and the display can be
programmed to turn red and flash a message on
alarm conditions. The meter can display the pump
runtimes and the number of times they have cycled.
See the Pump Control with Alternation & Alarm
Example on page 49 for full details.
Relay #2 turns the main pump on at 6000 gallons and
turns it off at 1000 gallons. lights up to show relay
2 is energized. The indicates level is rising.
With the Pump Alternation feature activated, the next
time the level reaches 6000 gallons, relay #1 transfers
and starts the backup pump. lights up to show
relay 1 is on.
Input Signal Conditioning
To satisfy applications that require scaling in ways
other than the usual 2-point linear method, the
PD6908 can also be scaled for square root (DP flow),
programmable exponent (open channel flow) or round
horizontal tank volume calculation.
Round Horizontal Tank
Linearization
This function automatically calculates the volume in a
round horizontal tank with flat ends and allows that
reading to be displayed on the bottom display. This
results in a meter that displays the height of the tank
on the top display and volume on the lower display.
The user only needs to enter the diameter and length
of the tank and the meter takes care of the rest.
Square Root Linearization
The square root function can be used to linearize the
signal from a differential pressure transmitter and
display flow rate in engineering units.
Programmable Exponent
Linearization
The programmable exponent can be used to linearize
the signal from level transmitters in open-channel flow
applications using weirs and flumes.
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Ordering Information
Hazardous Area Instruments
ProtEX+ PD6908 • Decimal Models – Aluminum Enclosure
Model
Description
PD6908-HA-AL-LNN
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, No Options
PD6908-HA-AL-L2N
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, Two Solid-State Relays
PD6908-HA-AL-L3N
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, 4-20 mA Analog Output
PD6908-HA-AL-L5N
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, Two Solid-State Relays
& 4-20 mA Analog Output
ProtEX+ PD6908 • Decimal Models – Stainless Steel Enclosure
Model
Description
PD6908-HA-SS-LNN
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, No Options
PD6908-HA-SS-L2N
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, Two Solid-State Relays
PD6908-HA-SS-L3N
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, 4-20 mA Analog Output
PD6908-HA-SS-L5N
Loop-Powered Explosion-Proof & Intrinsically Safe Process Meter, Two Solid-State Relays
& 4-20 mA Analog Output
Notes:
1. All models come with bargraph, two open collector outputs, and one digital input standard.
2. The meter comes standard with two ¾" NPT conduit holes. To order models with M20 conduit holes instead, add -21 at the end
of the part number (e.g. PD6908-HA-AL-LNN-21)
Accessories
Model
Description
PD659
Signal Isolators, Splitters, and Conditioners
PD9501
Multi-Function Calibrator
PD9502
Low-Cost Signal Generator
PDA1002
6" DIN Rail Mounting Kit
PDA1024-01
24 VDC Transmitter Power Supply for DIN Rail
PDA6846
Steel 2" U-Bolt Kit. All Material: Zinc Plated Steel; (1) U-Bolt for 2" Pipe with (2) Washers,
(2) Lock Washers, and (2) Nuts
PDA6846-SS
Stainless Steel 2" U-Bolt Kit. All Material: Stainless Steel; (1) U-Bolt for 2" Pipe with (2) Washers,
(2) Lock Washers, and (2) Nuts
PDAPLUG75
3/4" NPT 316 Stainless Steel Conduit Plug with Approvals
PDARED-M75-F50
M-3/4" NPT to F-1/2" NPT Reducer with Approvals
PDARED-M75-FM20
M-3/4" NPT to F-M20 Reducer with Approvals
PDA-SSTAG
Custom Stainless Steel Tag (see website for convenient ordering form)
• Accessories do not carry hazardous area approvals unless otherwise specified and are thus not suitable for
location in hazardous areas. The use of additional protective devices may allow them to be installed in a safe
area and connected to a device in a hazardous area. User should consult a professional engineer to determine
suitability of these products for their specific application.
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PDA1024-01 24 VDC Power Supply
The PDA1024-01 is a DIN rail mounted 1.5 A,
24 VDC power supply that can be used to power
the 4-20 mA transmitter.
PDA6846 2" U-Bolt Kits
The PDA6846 U-Bolt Kits provide a convenient way to
mount the meter to 1.5" or 2" pipes. They are
available in steel and stainless steel.
PDA-SSTAG Stainless Steel Tag
The PDA-SSTAG is a laser etched stainless steel tag
that can be customized with three lines of text.
Each tag comes with a stainless steel wire and lead
seal for easy mounting wherever you need.
PD9501 Multi-Function Calibrator
This PD9501 Multi-Function Calibrator has a variety
of signal measurement and output functions, including
voltage, current, thermocouple, and RTD.
PD9502 Low-Cost Signal Generator
The PD9502 is a low-cost, compact, simple to use
4-20 mA or 0-10 VDC signal generator. It can easily
be set for 0-20 mA, 4-20 mA, 0-10 V or 2-10 V
ranges. Signal adjustment is made with a one-turn
knob. A wall plug is provided with the instrument.
Optional USB power bank is available.
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Specifications
Except where noted all specifications apply to operation at +25°C.
Display
Display
Dual-line LCD with backlight.
Both lines: alphanumeric
Top: 0.7" (17.8 mm) 5 digits, 12-segment
Bottom: 0.4" (10.2 mm) 8 characters,
14-segment
Display may be programmed to turn red and
flash a user-defined message on
alarm condition.
On-Screen
Indicators
See CapTouch Buttons and Status Indicators
on page 27 for details.
Top Display
5 digits (-9999 to 99999) or 5 characters
Bottom
Display
8 digits (-9,999,999 to 99,999,999; separated
by commas) or 8 characters
(all capital & most lower-case letters)
Backlight
Powered by 4-20 mA loop
Intensity varies with signal level
Bargraph
20 segments
Decimal Point
Up to four decimal places on top display and
up to seven decimal places on bottom display
Commas
Commas to indicate 1000s
(e.g. 88,987,628) on the bottom display only
Dual-Scale
Feature
The input can be displayed in different scales
on the top and bottom displays. For instance,
the top display could display the input in
height units and the bottom display could
show that same input in volume units.
Alarm
Indication
Programmable: loop-powered red backlight,
flashing display, alarm symbol , bargraph
segment flashes on alarm.
Custom
Alarm
Messages
Programmable for each relay/open collector:
8 characters maximum; displayed every 10 sec for
1 sec on bottom display. May be turned off.
Display
Update Rate
Ambient > -10°C: 1 Update/Second
Ambient = -20°C: 1 Update/2 Seconds
From -20°C to -40°C the update rate slows
down 1 second for every -2°C
(e.g. at -24°C, 1 update/4 seconds).
Overrange
Top: 99999; Bottom: 99,999,999 (flashing)
Underrange
Top: -9999; Bottom: -9,999,999 (flashing)
General
Programming
Method
Four CapTouch through-glass buttons when
cover is installed. The CapTouch buttons can
be used with the cover removed.
Free PC-based USB MeterView XL
programming software.
Environmental
Operating temperature range:
-40 to 75°C (-40 to 167°F)
Storage temperature range:
-55 to 85°C (-67 to 185°F)
Installation temperature range:
-55 to 75°C (-67 to 167°F)
(The display ceases to function, however
inputs and outputs continue to operate)
Relative humidity: 0 to 90% non-condensing
Printed circuit boards are conformally coated
Noise Filter
Averages the input signal over a period of
time between 1 and 16 seconds to dampen
the effects of a noisy signal that causes a
jumpy display.
Filter Bypass
0.0 to 99.9% of full scale. Input signal
changes that are greater than the bypass
value are displayed immediately.
Recalibration
Recalibration is recommended at least every
12 months.
Max / Min
Display
Max / min readings reached by the process
are stored until reset by the user or until
power to the meter is turned off.
Tare
Tare function zeros out the meter to remove
the weight of a container.
Tare function can be assigned to a function
key or the digital input.
Password
Programmable password restricts
modification of programmed settings.
Non-Volatile
Memory
All programmed settings are stored in nonvolatile memory for a minimum of ten years if
power is lost.
Normal Mode
Rejection
64 dB at 50/60 Hz
Connections
Removable screw terminal blocks
Display terminals: accept 16 to 30 AWG wire
Relay terminals: accept 12 to 26 AWG wire
4-20 mA output: accept 16 to 30 AWG wire
Tightening
Torque
Display terminals: 2.5 lb-in (0.28 Nm)
Relay terminals: 4.5 lb-in (0.5 Nm)
4-20 mA output terminals: 2.5 lb-in (0.28 Nm)
Overall
Dimensions
5.25" x 5.65" x 4.80" (133 x 144 x 122 mm)
(W x H x D)
Weight
Aluminum: 5.1 lbs (2.3 kg)
Stainless Steel: 9.4 lbs (4.3 kg)
Warranty
3 years parts and labor. See Warranty
Information and Terms & Conditions on
www.predig.com for complete details.
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Enclosure
Material
AL Models:
ASTM A413 LM6 die-cast aluminum,
copper-free, enamel coated.
-SS Models:
ASTM A743 CF8M investment-cast
316 stainless steel
Gasket
Fluoroelastomer
Rating
NEMA 4X, IP68 Explosion-proof
Color
-AL: Blue; -SS: Silver
Window
Borosilicate glass
Conduits
Two ¾" NPT threaded conduit openings.
M20 conduits are available. See Ordering
Information on page 11 for details.
Flange
Built-in flange for wall and pipe mounting.
Tamper-Proof
Seal
Enclosure lid may be secured with
tamper-proof seal.
ATEX &
IECEx
(Enclosure
only)
Flameproof protection
II 2GD
Ex db IIC Gb
Ex tb IIIC Db
IP66/IP68
Tamb: -55°C to +85°C
Certificate No.: Sira 19ATEX1252U
Certificate No.: IECEx SIR 19.0075U
CSA
(Enclosure
only)
Class I, Division 1, Groups A, B, C, D
Class II, Division 1, Group E, F, G;
Class III
Ex db IIC Gb
Ex tb IIIC Db
Class I, Zone 1, AEx db IIC Gb;
Zone 21, AEx tb IIIC Db
IP66/IP68/TYPE 4X
Tamb: -55°C to +85°C
Certificate No.: 80011200
UL
(Enclosure
only)
Class I, Division 1, Groups A, B, C and D
Class II, Division 1, Groups E, F and G
Class III;
Class I, Zone 1, AEx db IIC Gb
Zone 21, AEx tb IIIC
Ex db IIC Gb
Ex tb IIIC Db
IP66/IP68/TYPE 4X
Tamb: -55°C to +85°C
Certificate Number: E518920
Input
Input
4-20 mA
Accuracy
±0.02% of span ±1 count,
Square root and programmable exponent:
10-100% FS
Voltage Drop
Without backlight: 1.5 V maximum,
With backlight: 4.7 V maximum
Equivalent
Resistance
Without backlight: 75 Ω @ 20 mA
With backlight: 235 Ω @ 20 mA
Input
Overload
Over current protection to 1 A maximum,
Over voltage protection to 30 VDC max
(Between mA+ and mA- / BL-)
Temperature
Drift
25 PPM/°C from -40 to 75°C ambient
Function
PV1: Linear (2-32 points), square root, or
programmable exponent
PV2: Linear (2-32 points) or round horizontal
tank
Low-Flow
Cutoff
0.1 to 999,999 or disable. Point below at which
the display always shows zero.
HART
Transparency
The meter does not interfere with existing
HART communications; it displays the
4-20 mA primary variable and it allows the
HART communications to pass through
without interruption. The meter is not affected if
a HART communicator is connected to the
loop. The meter does not display secondary
HART variables.
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Common Open Collector & Relay Specifications
Number
Two open collectors & two relays
High or Low
Alarm
User programmable for high or low alarm
Alarm
Deadband
0-100% FS, user programmable
Output
Assignment
Alarm, Timer, Stopwatch, or Disable
Alarm Output
Source
Assign to PV (PV1, PV2) or Digital Input
On & Off Time
Delay
0 to 9,999 seconds
Fail-Safe
Operation
Independent for each open collector and
relay.
Fail-safe on, the output is on under normal
conditions.
Fail-safe off, the output is on under alarm
conditions.
Alarm
Operation
Automatic, automatic with manual override,
latching (manual reset anytime), latching with
reset after cleared (manual reset only after
alarm has cleared)
Alarm
Indication
Programmable: loop-powered red backlight,
flashing display, alarm symbol , bargraph
segment flashes on alarm.
Custom
Alarm
Messages
Programmable for each relay/open collector:
8 characters maximum; displayed every 10 sec for
1 sec on bottom display. May be turned off.
Alarm
Acknowledge
CapTouch ACK button or external digital
input resets output and screen indication.
Auto
Initialization
When power is applied to the meter, open
collectors and relays will reflect the state of
the input to the meter.
Timer Output
One-shot or Continuous
Off Time Delay: 1 sec to 99:59:59
(hrs:min:sec)
On Time: 1 sec to 99:59:59 (hrs:min:sec)
Stopwatch
Output turns on when started and off when
stopped.
Open Collector Outputs
Rating
Isolated open collector, sinking NPN
5-30 VDC @ 150 mA maximum
Output
Assignment
Pulse, Alarm, Timer, Stopwatch, or Disable
Pulse Output
Source
PV (PV1, PV2) or Test Frequency
Pulse Output
Factor
0.000001 to 999,999.9
Pulse Width
0.5 ms @ 1 kHz; 500 ms @ 1 Hz;
50% duty cycle
Pulse Output
Frequency
1,000 Hz maximum
Quadrature
Pulse Output
Available for Output 2
(90° behind Output 1) 500 Hz max
Alarm Output
Source
Assign to PV (PV1, PV2)
or Digital Input
Solid-State Relays
Rating
250 VAC/VDC @ 0.5 A resistive
38 VA; 250 VAC; 0.3 A pilot duty
(inductive)
13 VA; 250 VDC; 0.3 A pilot duty (inductive)
Noise
Suppression
Metal oxide varistors across outputs
Relay
Assignment
Pump Alternation, Alarm, Timer, Stopwatch
on/off, or Disable
Alarm Output
Source
Assign to PV (PV1, PV2) or Digital Input
Pump
Alternation
Relays may be programmed to alternate with
each pump cycle with an elapsed time
override where the pumps will alternate
regardless of level. Pump alternation time
can be programmed for 0 to 999:59 (hrs:min)
Relay (Pump)
Runtime
Meter will keep track of how long each relay
(pump) has operated and display this
information.
Relay (Pump)
Cycles
Meter will keep track of how many times the
relays (pumps) have cycled and display this
information.
4-20 mA Transmitter Output
Accuracy
±0.05% FS ±0.001mA
Output
Source
PV1, PV2, re-transmit; reverse scaling
allowed
Scaling
Range
1.00 to 23.0 mA
Disable
High impedance state, less than 1 mA
Calibration
Factory calibrated 4.00 to 20.00 mA
Underrange
1.0 mA, 3.5 mA, or 3.8 mA
(If input < 3.5 mA); or disable underrange;
user selectable
Overrange
20.5 mA, 20.8 mA, or 23.0 mA
(If input > 20.5 mA); or disable overrange;
user selectable
Isolation
500 V input-to-output
Temperature
Drift
0.5 µA/°C max from -40 to 75°C ambient
External Loop
Power Supply
7.0 VDC to 30.0 VDC maximum
Output Loop
Resistance
10-750 Ω @ 24 VDC; 10-1100 Ω @ 30 VDC
On-Board Digital Input
Function
Remote acknowledge/reset relays, reset
max/min values, etc. See User section of
Display Functions & Messages on page 28
for a complete list of capabilities.
Contacts
2.1 VDC on contact. Connect normally open
contacts across DI+ and DI-
Logic Levels
Logic High: 2.4 to 30 VDC (max)
Logic Low: 0 to 0.9 VDC
Page 16
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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MeterView XL Software
Availability
Free download from www.predig.com
System
Requirements
Microsoft® Windows® 7 & 10
Communicati
ons
USB 2.0 (Standard USB A to Micro USB B)
Cable provided
Configuration
Configure all parameters on the meter.
Configure meters one at a time.
Configuration
Files
Generate with or without meter connected;
Save to file for later use.
USB Power
Connection
Meter is powered by USB connection during
programming, if 4-20 mA loop is not
connected.
• The meter should only be connected to a
computer while it is located in a safe area.
To download the latest MeterView XL programming
software and manual, visit predig.com/meterviewxl.
Page 17
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Compliance Information
Hazardous Area Approvals
CSA
Explosion-proof for use in:
Class I, Division 1, Groups B, C and D
Dust-ignition proof for use in:
Class II/III, Division 1, Groups E, F and G; T6
Flame-proof for use in:
Zone 1, Ex d IIC T6
Ta = -55 to 75°C.
Enclosure: Type 4X & IP66/IP68.
Certificate number: 2325749
ATEX
II 1 G D
Ex ia IIC T4 Ga
Ex ia IIC T200°C Da
Ta = -40 to 75°C
Enclosure: Type 4X & IP66/IP68
Install per Control Drawing DW2636
(contained within LIM6908-2)
Certificate number: CML 18ATEX2089X
IECEx
II 1 G D
Ex ia IIC T4 Ga
Ex ia IIC T200°C Da
Ta = -40 to 75°C
Enclosure: Type 4X & IP66/IP68
Install per Control Drawing DW2636
(contained within LIM6908-2)
Certificate number: IECEx CML 18.0050X
ATEX/IECEx Special Conditions for Safe Use
The following conditions relate to safe installation
and/or use of the equipment.
• The equipment loop/power port shall be connected
to an intrinsically safe barrier with Uo ≥ 5.8V
• The 4-20 mA input port shall be connected to an
intrinsically safe barrier with Uo ≥ 5.1V
• The PD6928-HA-AL enclosure is manufactured from
aluminum. In rare cases, ignition sources due to
impact and friction sparks could occur. This shall be
considered during installation, particularly if the
equipment is installed in a Zone 0 location.
• All cable entries into the equipment shall be via cable
glands or conduit which provide a minimum degree
of protection of IP54.
• The equipment may not have 500V isolation
between the circuit and earth. This shall be taken
into account when installing the equipment.
Year of Construction
This information is contained within the serial number
with the first four digits representing the year and
month in the YYMM format.
For European Community:
The PD69XX Series must be installed in accordance
with the ATEX directive 2014/34/EU, the product
certificates CML 18ATEX2089X, IECEx CML
18.0050X and the product manual.
Electromagnetic Compatibility
EMC Emissions
• CFR 47 FCC Part 15 Subpart B Class A
emissions requirements (USA)
• ICES-003 Information Technology
emissions requirements (Canada)
• AS/NZS CISPR 11 Group 1 Class A
ISM emissions requirements
(Australia/New Zealand)
• EN 55011 Group 1 Class A ISM
emissions requirements (EU)
• EN 61000-6-4 Emissions requirements
for Heavy Industrial Environments Generic
EMC Emissions
and Immunity
EN 61326-1 EMC requirements for
Electrical equipment for measurement,
control, and laboratory use – industrial use
Page 18
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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EU Declaration of
Conformity
For shipments to the EU and UK, a Declaration of
Conformity was printed and included with the product.
For reference, a Declaration of Conformity is also
available on our website www.predig.com/docs.
Safety Information
• Read complete instructions prior to installation
and operation of the meter.
• Hazardous voltages exist within enclosure.
Installation and service should be performed only
by trained service personnel.
• Service requiring replacement of internal
components must be performed at the factory.
• Control room equipment must not use or
generate more than 250 VRMS or VDC.
• Hazardous location installation instructions for
associated apparatus (barrier) must be followed
when installing this equipment.
• For safe installation of an ATEX approved
transmitter in series with PD6908 loop-powered
process meters, the hazardous location
installation instructions for the transmitter,
PD6908 loop-powered process meter, and
associated apparatus (barrier) must be
compatible.
• PD6908 loop-powered process meters do not
add capacitance or inductance to the loop under
normal or fault conditions.
• Substitution of components may impair
hazardous location safety.
• Equipment contains non-metallic materials and
therefore special care and consideration should
be made to the performance of these materials
with respect to chemicals which may be present
in a hazardous environment.
Installation
To access the connectors, remove the enclosure
cover and unclip the display module by pulling it from
the enclosure. The display module may be
disconnected from the options module to facilitate
wiring to the options module.
Refer to Control Drawing DW2636 (contained within
LIM6908-2) for details related to intrinsically safe field
wiring.
Explosion-Proof / Dust-Ignition Proof / Flame-Proof
• Disconnect from supply before opening
enclosure. Keep cover tight while circuits are live.
Conduit seals must be installed within
18" (450mm) of the enclosure.
Unpacking
Remove the meter from box. Inspect the packaging
and contents for damage. Report damages, if any,
to the carrier.
If any part is missing or the meter malfunctions,
please contact your supplier or the factory for
assistance.
Page 19
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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Mounting
The PD6908 has a slotted mounting flange that may
be used for pipe mounting or wall mounting.
Alternatively, the unit may be supported by the
conduit using the conduit holes provided. Refer to
Figure 1 and Figure 2.
• Do not attempt to loosen or remove flange bolts
while the meter is in service.
Dimensions
All units: inches [mm]
Figure 1. Enclosure Dimensions – Front View
Figure 2. Enclosure Dimensions – Side View
Figure 3. Enclosure Dimensions – Top View
Cover Jam Screw
The cover jam screw should be properly installed
once the meter has been wired and tested in a safe
environment. The cover jam screw is intended to
prevent the removal of the meter cover in a flameproof environment without the use of tools. Using a
M2 hex wrench, turn the screw clockwise until the
screw contacts the enclosure’s base. Turn the screw
an additional 1/4 to 1/2 turn to secure the cover.
• Excess torque may damage the threads, screw
head, and/or wrench.
5.25" (133 mm)
3.35" (85.1 mm)
2.25"
(57.2 mm)
0.32"
(8.2 mm)
5.65"
(144 mm)
4.80"
(122 mm)
Page 20
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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Connections
To access the connectors, remove the enclosure cover and unclip the display module by pulling it from the enclosure.
Signal, backlight, open collector, and digital input connections are made to removable connectors on the display
module. Relays and 4-20 mA output connections (if installed) are made to removable connectors on the options
module mounted in the base of the enclosure. The display module may be disconnected from the options module to
facilitate wiring to the options module. Grounding connections are made to the two ground screws provided on the
base of the enclosure, one internal and one external.
• Observe all safety regulations. Electrical wiring should be performed in accordance with all agency
requirements and applicable national, state, and local codes to prevent damage to the meter and ensure
personnel safety.
• Static electricity can damage sensitive components.
• Observe safe handling precautions for static-sensitive components.
• Use proper grounding procedures/codes.
• If the meter is installed in a high voltage environment and a fault or installation error occurs, high voltage may
be present on any lead or terminal.
Display & Options Modules
The display module snaps into built-in rails on the enclosure ensuring a secure and perfect fit every time. No tools are
needed to install or remove it. The options module is screwed into the base of the enclosure. Both modules
completely encase the printed circuit boards.
Options Board (Left) and Display Module (Right)
Options Board Connected to Display Module
Options Board Mounted on the Bottom of Enclosure
Display Module Mounted on Built-In Rails
Page 21
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Connectors Labeling
The following graphics show the locations of the connectors for each available configuration.
Figure 4. Connector Labeling for PD6908-HA-##-LNN
Figure 5. Connector Labeling for PD6908-HA-##-L2N
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal
Options Board
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
NO
C NO
C
Solid State
Relay 2
Solid State
Relay 1
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal
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Figure 6. Connector Labeling for PD6908-HA-##-L3N
Figure 7. Connector Labeling for PD6908-HA-##-L5N
Options Board
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
4-20 mA
Output
+
–
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal
Options Board
USB
Connection
CapTouch
On/Off
Switch
Ribbon Cable
Connector
–+
OC2
–+
OC1
Open Collector
Outputs
NO
C NO
C
Solid State
Relay 2
Solid State
Relay 1
4-20 mA
Output
+
–
DI BL mA
–+–+–
Digital
Input
Backlight
+ Signal
Page 23
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Wiring Diagrams
Intrinsically Safe Wiring
• PD6908 installation must be performed in
accordance with control drawings included in the
LIM6908-2, in order to meet agency approval
ratings.
• For ATEX certification, barrier and transmitter
must be ATEX Certified with Entity Parameters
and must be connected per manufacturer’s
instructions.
• Service requiring replacement of internal
components must be performed at the factory.
• Entire meter assembly (electronic assembly) may
be replaced in the field with a unit supplied from
the factory labeled “Field Modification”.
I/O Parameter Table
4-20 mA Loop Input
Switch Port
Ui = 30 V
Ui = 30 V
Ii = 175 mA
Ii = 175 mA
Pi = 1 W
Pi = 1 W
Ci = 0
Ci = 0
LI = 0
LI = 0
Open Collector Outputs
Backlight Terminal
Ui = 30 V
Ui = 30 V
Ii = 175 mA
Ii = 175 mA
Pi = 1 W
Pi = 1 W
Ci = 0
Ci = 0
LI = 0
LI = 0
Power Supply Input
mA Output
Ui = 30 V
Ui = 30 V
Ii = 175 mA
Ii = 175 mA
Pi = 1 W
Pi = 1 W
Ci = 0
Ci = 0
LI = 0
LI = 0
Relay Outputs
Ui = 30 V Ii = 1000 mA
Pi = 1 W
Ci = 0.013 uF
LI = 0
Uo = 11.55 V
Io = 1 mA
Po = 0.012 W
Explosion-Proof Wiring
Current Loop (4-20 mA) Connections
Signal connections are made to a three-terminal
connector. See Connectors Labeling on page 21. The
following figures show a 4-20 mA current loop
connected to the meter. Figure 8 shows the
connection without the backlight and Figure 9 shows
the connection with the backlight (the backlight can be
disabled/enabled in the SYSTEM menu, if connected).
The meter and the backlight are powered by the
4-20 mA current loop.
There are no switches or jumpers to set up for the
input. Setup and programming are performed through
the CapTouch buttons or PC-based software.
Figure 8. 4-20 mA Input Connection without Backlight
Figure 9. 4-20 mA Input Connection with Backlight
The current input is protected against current
overload up to 1 amp. The display may or may not
show a fault condition depending on the nature of the
overload.
--+
BL mA
4-20 mA
Transmitter
+-
Power
Supply
+
-
--+
BL mA
4-20 mA
Transmitter
+-
Power
Supply
+
-
Page 24
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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Digital Input Connections
A digital input is standard on the meter. This digital
input is connected with a normally open contact
across DI+ and DI-, or with an active low signal
applied to DI+ and DI-.
Figure 10. Digital Input Connections
4-20 mA Output Connections
Connections for the 4-20 mA transmitter output are
made to the connector terminals labeled 4-20 mA
Output on Figure 6, on page 22. The 4-20 mA output
must be powered from an external power supply.
Figure 11. 4-20 mA Output Connections
Solid-State Relay Connections
Relay connections are made to two-terminal
connectors, as shown on Figure 5, page 21. Each
relay’s C terminal is common only to the normally
open (NO) contact of the corresponding relay.
Figure 12. Solid-State Relay Connections
Open Collector Output Connections
Open collector output 1 and 2 connections are made
to terminals labeled OC1 and OC2 on Figure 4, page
21. Connect the alarm or pulse input device as shown
below.
Figure 13. Open Collector Output Connections
-+
DI
-+
Device with
4-20 mA
Input
-+
Power
Supply
+-
CNO
CNO
Load
Load
Power
Relay 1
Relay 2
Power
Supply
-+
-++-
OC2 OC1
Alarm
Indicator/
Pulse
Counter
+
-
External DC
Relay
5-30 VDC
150 mA MAX
Page 25
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Setup and Programming
The meter is factory calibrated prior to shipment to display
0.00 to 100.00, which corresponds to the 4-20 mA input.
The calibration equipment is traceable to NIST standards.
Overview
There are no jumpers to set; setup and programming
is done through the CapTouch buttons or the free
MeterView XL PC-based software.
The meter may be powered via the micro-USB
connection located on the display module for the
purpose of programming only. The backlight will not
work while the meter is powered via the USB
connection.
CapTouch Buttons
The PD6908 is equipped with four capacitive sensors
that operate as through-glass buttons so that it can be
programmed and operated without removing the
cover (and exposing the electronics) in a hazardous
area.
These buttons can be disabled for security by
selecting the Lock setting on the switch located on the
side of the display module, close to the Menu button.
To actuate a button, press one finger to the glass
directly over the marked button area. When the cover
is removed, the CapTouch buttons can be used after
the meter completes a self-calibrating routine (hand
symbol flashes). The sensors are disabled when more
than one button is pressed, and they will automatically
re-enable after a few seconds (hand symbol off).
CapTouch Buttons Delay
The CapTouch have two modes of operation: Normal and
Delayed. Use the Delayed mode to prevent accidental
trigger of the buttons. In the Delayed mode, the buttons
enter into a low sensitivity state (sleep) and they ignore quick
button presses after 20 seconds of inactivity. To wake up the
buttons, press and hold any button for more than 2 seconds,
the buttons respond normally.
Disabling the CapTouch Buttons
The CapTouch buttons can be disabled by moving the slide
switch, located on the display module to the Lock position;
see the image below.
CapTouch Button Tips & Troubleshooting
The CapTouch buttons are designed to work under
any lighting condition and to protect against false
triggering. If the CapTouch buttons are not needed
during operation, they can be disabled (slide switch to
Lock).
• To remove cover with power applied (safe area
only), or to clean the window, place your hand
over the buttons; this will temporarily disable the
CapTouch buttons to prevent inadvertent use.
• Keep the glass window clean.
• Tighten the cover securely.
• Use a password to prevent tampering.
• CapTouch buttons will not work if two or more
buttons are detected as being pressed
simultaneously. Be careful to avoid triggering
multiple buttons or reaching across one button
location to press another.
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PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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MeterView XL Programming Software
The fastest and easiest way to program the meter is
using the free Meterview XL programming software.
This software greatly simplifies the programming
process and allows the user to save configuration files
for later use.
The meter connects to the PC via a provided microUSB cable and is powered by the USB connection, so
no additional power is needed during programming.
To download the latest MeterView XL programming
software and manual, visit predig.com/meterviewxl.
• The meter should only be connected to a
computer while it is located in a safe area.
• Care should be exercised to avoid ground loops
when connecting the USB to an active loop (e.g.
power supply, transmitter, loop-powered meter,
etc.). It is recommended to connect the (mA+)
terminal of the meter to the (-) terminal of a twowire transmitter and the (mA-) to the (+) of the
next device in the loop or to the (-) terminal of the
power supply.
Page 27
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CapTouch Buttons and Status Indicators
Buttons
Button
Description
Menu
Right Arrow/F1
Up Arrow/F2
Enter/F3
1. Press the Menu button to enter or exit the
Programming Mode at any time.
2. Press or hold the Right-Arrow button to scroll
forward through the menus, select digits during
numeric programming, select characters during
text programming, or decrement the value of a
digit or character selected with the Up-Arrow
button.
3. Press and hold the Right-Arrow button to zero or
clear digits/characters while in data-entry mode.
4. Press or hold the Up-Arrow button to scroll
backwards through the menus or to increment
the value of a digit or character.
5. Press the Enter button to access a menu or to
accept a setting or programmed digit/character
value.
Indicators
Indicator
State
Description
Steady
Process trend arrows
Flashing
Alarm Indicator
Steady
Password protected
Steady
Solid-state relay 1
Steady
Solid-state relay 2
Flashing
CapTouch buttons
self-calibrating (wait)
Steady
PV Bargraph
Flashing
Alarm condition:
Bargraph segment flashes
on alarm
Units
Display
Units
Top
rev, lb, ton, ft3, bbl, m3, kg, US GAL, IGAL,
GAL, GAL/hr, GAL/sec, GAL/min, GAL/day,
° (degree), % (percent)
Bottom
lb, m3, ton, bbl, ft3 kg, US GAL, IGAL, GAL
• Avoid touching more than one button at a time,
otherwise the buttons become unresponsive and
enter into a self-calibrating routine. This is
indicated by the flashing hand symbol .
Page 28
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Display Functions & Messages
The meter displays various functions and messages during
setup, programming, and operation. The following table
shows the main menu functions and messages in the order
they appear in the menu.
Display Functions & Messages
Parameter
Action/Setting Description
INPUT (PV1 and PV2)
Program the meter 4-20 mA input
(two menus, PV1 and PV2, are
available if in dual-scale mode;
see PV2 under advanced features
menu)
SCALE PV (1 or 2)
Scale the selected PV
UNITS
Select the display units
VOLUME
Volume unit class
GAL
Gallons
L
Liters
IGAL
Imperial Gallons
M3
Cubic Meters
BBL
Barrels
BUSH
Bushels
cuYD
Cubic Yards
cuFt
Cubic Feet
cuIn
Cubic Inches
LiBBL
Liquid barrels
BBBL
Beer barrels
HECtL
Hectoliter
AF
Acre-Foot
CUSTM
Custom Unit
HEIGHT
Height unit class
INCH
Inches
FEET
Feet
YARD
Yards
CM
Centimeters
M
Meters
CUSTOM
Custom unit
TEMP
Temperature unit class
~F
Degrees Fahrenheit
~C
Degrees Celsius
K
Kelvin
~RA
Degrees Rankine
PRESSURE
Pressure unit class
PSI
Pounds per square inch
InHg
Inches of mercury
InH2O
Inches of water
mmHg
Millimeters of mercury
Kg/CM2
Kilograms per square centimeter
Kg/M2
Kilograms per square meter
mBAr
Millibar
Bar
Bar
Display Functions & Messages
Parameter
Action/Setting Description
PA
Pascal
hPA
Hectopascal
KPA
Kilopascal
MPA
Megapascal
CUSTM
Custom unit
WEIGHT
Weight unit class
gm
Grams
Kg
Kilograms
tonnE
Tonnes (metric)
oz
Ounces
1b
Pounds
ton
Tons
CUSTOM
Custom unit
RATE
Rate unit class
/SECOND
Units per second
/MINUTE
Units per minute
/HOUR
Units per hour
/DAY
Units per day
GAL/(T)
Gallons per time unit (T)
L/(T)
Liters per time unit (T)
IGAL/(T)
Imperial gallons per time unit (T)
M3/(T)
Cubic meters per time unit (T)
BBL/(T)
Barrels per time unit (T)
BUSH/(T)
Bushels per time unit (T)
cuYD/(T)
Cubic Yards per time unit (T)
cuFt/(T)
Cubic Feet per time unit (T)
cuIn/(T)
Cubic Inches per time unit (T)
LiBBL/(T)
Liquid barrels per time unit (T)
BBBL/(T)
Beer barrels per time unit (T)
HECtL/(T)
Hectoliter per time unit (T)
AF/(T)
Acre-Foot per time unit (T)
CUSTOM/
Custom unit per time unit (T)
CUSTOM
Custom unit class
C.UNIT
Custom unit
INPUT 1
Program input 1 value
INP 1
Enter the input 1 value
DISP 1
Program display 1 value
DSP 1
Enter the display 1 value
INPUT 2
Program input 2 value
(up to 32 points)
INP 2
Enter the input 2 value
DISP 2
Program display 2 value
(up to 32 points)
DSP 2
Enter the display 2 value
SAVE?
Press Enter to save programmed
units, input, and display values.
Press Menu to cancel.
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Display Functions & Messages
Parameter
Action/Setting Description
OUTPUT
Press Enter to save
programmed units, input, and
display values. Press Menu to
cancel.
OPEN COLLECTR
Program the meter’s open
collector outputs
OUTPUT1
Open collector 1 setup
OUTPUT2
Open collector 2 setup
DISABLE
Disable the open collector
PULSE
Program the open collector for
pulse output
ALARM
Program the open collector for
alarm output
TIMER
Program the open collector as a
timer
STPWATCH
Program the open collector to turn
on while the stopwatch is running
RELAY
Program the meter’s relay outputs
OUTPUT1
Relay 1 setup
OUTPUT2
Relay 2 setup
DISABLE
Disable the relay
ALARM
Program relay for alarm
functionality
PUMPCTRL
Program relay for pump control
application
TIMER
Program relay as a timer
STPWATCH
Program relay to turn on while the
stopwatch is running
RELAY INFO
View relay runtime and cycle count
4-20 Ma
Program the meter’s 4-20 mA
output
PV
Program a range to transmit based
on the display value
RETRANS
Retransmit the mA input signal
DISABLE
Disable the 4-20 mA output
CONTROL
Program manual or automatic
operation for the outputs
OC1
Open collector 1
OC2
Open collector 2
RELAY1
Relay 1
RELAY2
Relay 2
4-20 mA
4-20 mA output
AUTO
Set selected output to automatic
operation
MANUAL
Manually control selected output
operation
ADVANCE
Program the meter’s advanced
features
PV SETUP
(PV 1 & PV 2)
Advanced input programming
(two menus, PV 1 and PV 2, are
available if in dual-scale mode;
see PV 2 under advanced
features menu)
Display Functions & Messages
Parameter
Action/Setting Description
SOURCE
Select PV 2 source (dual-scale
only; see PV 2 under advanced
features menu)
4-20 ma
Source PV 2 from the mA input
PV1
Source PV 2 from PV 1
FUNCTN
Select linear, square root, or
programmable exponent function
LINEAR
Set meter for linear function and
select number of linearization
points
SQROOT
Set meter for square root
extraction
EXPONENT
Set meter for programmable
exponent and enter exponent
value
RH TANK
Round horizontal tank (dual-scale
only; see PV2 under advanced
features menu)
SCALE.CAL
Scale or calibrate the mA input
SCALE PV
Scale the input
CAL PV
Calibrate the input
CUTOFF
Set low-flow cutoff
DISABLE
Disable low-flow cutoff
ENABLE
Enable low-flow cutoff
FILTER
Set noise filter value
1.0 SEC
1 second
2.0 SEC
2 seconds
4.0 SEC
4 seconds
8.0 SEC
8 seconds
16.0 SEC
16 seconds
OFF
Turn filter off
BYPASS
Set filter bypass (0.0 to 99.9% FS)
PASSWRD
Set a password for the meter
PASS MAIN
Program the main meter password
USER
Assign function keys / digital input
F1
Assign F1 function key
F2
Assign F2 function key
F3
Assign F3 function key
DI
Assign digital input
DISP FN
Set the function key or digital input
to display a value
DISPLAY
Cycle max, min, and PV(s)
DISP PV
Display the PV
PCT PV
Display the PV’s percentage of
max (20 mA)
D UNITS
Display the PV’s units
D TAG
Display the PV’s tag
DISPMIN
Display the PV’s minimum value
DISPMAX
Display the PV’s maximum value
MIN MAX
Display the PV’s minimum and
maximum value
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Display Functions & Messages
Parameter
Action/Setting Description
D mA IN
Display the current mA input value
D mAOUT
Display the current mA output
value
MENU FN
Set the function key or digital input
to access a menu
RLYINFO
Go to relay information menu
(INFO)
MANCTRL
Go to output control menu
(CONTROL)
TIMR OC1
Open collector 1 timer
TIMR OC2
Open collector 2 timer
TIMER R1
Relay 1 timer
TIMER R2
Relay 2 timer
TIMER.FN
Set the function key or digital input
to start or stop a timer
STRT.ALL
Start all timers
STOP.ALL
Stop all timers
S.STP.ALL
Start or stop all timers
OC1
Start/stop open collector 1 timer
OC2
Start/stop open collector 2 timer
RLY1
Start/stop relay 1 timer
RLY2
Start/stop relay 2 timer
START
Start the selected timer output
STOP
Stop the selected timer output
STR-STP
Start or stop the selected timer
output
ALARM.FN
Set the function key or digital input
to acknowledge an alarm or
access set points
ACK
Acknowledge all active alarms
SETPOINT
Access all output set points
SETPT.OC1
Access open collector 1 set point
SETPT.OC2
Access open collector 2 set point
SETPT.R1
Access relay 1 set point
SETPT.R2
Access relay 2 set point
SWATCH.Fn
Set the function key or digital input
to activate stopwatch
START
Start the stopwatch
STOP
Pause/Stop the stopwatch
STR-STP
Start or stop the stopwatch
TARE.FN
Set the function key or digital input
to tare the display
TARE
Tare the display value
RST TARE
Reset the display value
HOLD FN
Set the function key or digital input
to hold an output
HOLD.OUT
Hold all outputs
HLD.
UNHLD
Hold or un-hold all outputs
OC1+2
Hold/un-hold open collector
outputs
Display Functions & Messages
Parameter
Action/Setting Description
RLY1+2
Hold/un-hold relay outputs
mAOUT
Hold/un-hold 4-20 mA output
HOLD
Hold selected output
HLD.UNHLD
Hold or un-hold selected output
DISABLE
Disable function key or digital input
RST FN
Set the function key or digital input
to reset a value
RESET
Reset min, max, or max/min PV
R MIN.MAX
Reset max and min PV value
HINT
Display hint text on key press and
execute action on next key press
OFF
Turn the hint function off
ON
Turn the hint function on
SYSTEM
Program system settings
AOUTCAL
Calibrate the analog output
DEFAULT
Reset meter to factory defaults
PV 2
Enable the meter to scale a
second PV based on the same
4-20 mA input
DISABLE
Disable dual-scale feature (default)
ENABLE
Enable dual-scale feature
BACKLITE
Enable/disable display backlight
ENABLE
Enable the backlight (default)
DISABLE
Disable the backlight
CAPTOUCH
Select CapTouch buttons mode
NORMAL
CapTouch normal (default)
DELAYED
CapTouch delayed
INFO
View meter software version and
model; change the identifier tag
SFT
The software ID number
VER
The software version
MODEL
The meter model number
ID.TAG
The meter identifier tag
Press Enter to edit tag
ICAL
Internal calibration used for scaling
DISPLAY
Program the meter’s display
UNITS
Change the display units within the
selected unit class
DEC.PT
Change the decimal point location
COMMA
Enable or disable the use of a
comma on the bottom display
ENABLE
Enable comma (default)
DISABLE
Disable comma
BARGRAPH
Turn off or change the bargraph
PV (1 or 2)
Set the bargraph to display the
percentage of a user-selected range
PV PCT (1 or 2)
Set the bargraph to display the PV
percentage of full scale
OFF
Turn off the bargraph
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Display Functions & Messages
Parameter
Action/Setting Description
TOP
Select what to display on the top
display
PV (1 or 2)
Display the process variable
PV+UNIT (1 or 2)
Display the process variable and
units alternating
PV+TAG (1 or 2)
Display the process variable and
tag alternating
TAG+UNIT
Display tag and units alternating
PV+U+TAG (1 or 2)
Display the process variable, unit,
and tag alternating
PV1+PV2
Display both process variables
(dual-scale only; see PV 2 under
advanced features menu)
TAG
Display the tag
STPWATCH
Display the stopwatch
TIMR OC1
Display open collector 1 timer
TIMR OC2
Display open collector 2 timer
TIMER R1
Display relay 1 timer
TIMER R2
Display relay 2 timer
MIN
Display minimum value
MAX
Display maximum value
MIN MAX
Display alternating min and max
OFF
Turn top display off
UNITS
Display the units
BOTTOM
Select what to display on the
bottom display
UNITS
Display the units
PV (1 or 2)
Display the process variable
PV+UNIT (1 or 2)
Display the process variable and
unit alternating
PV+TAG (1 or 2)
Display the process variable and
tag alternating
TAG+UNIT
Display the tag and unit alternating
PV+U+TAG (1 or 2)
Display the process variable, unit,
and tag alternating
PV1+PV2
Display both process variables
(dual-scale only; see PV 2 under
advanced features menu)
TAG
Display the tag
STPWATCH
Display the stopwatch
TIMR OC1
Display open collector 1 timer
TIMR OC2
Display open collector 2 timer
TIMER R1
Display relay 1 timer
TIMER R2
Display relay 2 timer
OFF
Turn bottom display off
PV PCT (1 or 2)
Display the process variable
percentage of full scale
mA IN
Display the current mA input value
mA OUT
Display the current mA output
value
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Main Menu
The main menu consists of all the meter’s programmable functions: Input, Output, Advanced, and Display.
• Press Menu button to enter Programming Mode then press the Right-Arrow button to move forward through the
menu and the Up-Arrow button to move back.
• Press Menu at any time to go back one level or press & hold to exit and return to Run Mode. Changes made to
settings prior to pressing Enter are not saved.
• Changes to the settings are saved to memory only after pressing Enter/F3 to confirm the setting or pressing
Enter/F3 at the SAVE? screen when available.
Note: The navigation returns to the top
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Setting Numeric Values
The numeric values are set using the Right and Up-Arrow buttons.
1. Press Right-Arrow to select next digit and Up-Arrow to increment digit value. The selected digit will flash.
2. Press and hold Up-Arrow to auto-increment the display value. If you have made a mistake or would like to
enter a new value, select the left-most digit, and press and hold the Right-Arrow button until all digits reset
to zero.
3. Press the Enter button at any time to accept a setting or Menu button to exit without saving changes.
Note: the underscore in the graphic below is provided to show which digit would be flashing.
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Scaling the 4-20 mA Input (INPUT)
It is very important to read the following information before proceeding to program the meter:
• The meter is factory calibrated prior to shipment to display 0.00 to 100.00 gal, which corresponds to the 4-20 mA
input. The calibration equipment is traceable to NIST standards.
• A calibrated signal source is not needed to scale the meter.
Enter the Input menu to scale the meter to display the 4-20 mA input. The input can accept any signal from
4 to 20 mA.
• Reverse Scaling
The meter can be scaled so that 4 mA represents the high end of the process value range being measured by
the transmitter and 20 mA represents the low end of the process value range.
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Available Unit Classes and Units
The meter has six available preprogrammed unit classes: volume, height, temperature, pressure, weight, and rate.
Each unit class has the following available units to choose from:
Volume Units (VOLUME)
GAL
Gallons
L
Liters
IGAL
Imperial Gallons
M3
Cubic Meters
BBL
Barrels
BUSH
Bushels
cuYD
Cubic Yards
cuFt
Cubic Feet
cuIn
Cubic Inches
LiBBL
Liquid barrels
BBBL
Beer barrels
HECtL
Hectoliter
AF
Acre-Foot
CUSTOM
Custom Unit
Height Units (HEIGHT)
INCH
Inches
FEET
Feet
FT-IN
Feet & Inches
YARD
Yards
CM
Centimeters
M
Meters
CUSTOM
Custom unit
Temperature Units (TEMP)
~F
Degrees Fahrenheit
~C
Degrees Celsius
K
Kelvin
~RA
Degrees Rankine
Pressure Units (PRESSURE)
PSI
Pounds per square inch
InHg
Inches of mercury
InH2O
Inches of water
mmHg
Millimeters of
mercury
Kg/CM2
Kilograms per square centimeter
Kg/M2
Kilograms per square meter
mBAr
Millibar
Bar
Bar
PA
Pascal
hPA
Hectopascal
KPA
Kilopascal
MPA
Megapascal
CUSTOM
Custom unit
Weight Units (WEIGHT)
gm
Grams
Kg
Kilograms
tonnE
Tonnes (metric)
oz
Ounces
1b
Pounds
ton
Tons
CUSTOM
Custom unit
Rate Time Bases (TIME)
/SECOND
Units per second
/MINUTE
Units per minute
/HOUR
Units per hour
/DAY
Units per day
Rate Units (RATE)
GAL/(T)
Gallons per time unit (T)
L/(T)
Liters per time unit (T)
IGAL/(T)
Imperial gallons per time unit (T)
M3/(T)
Cubic meters per time unit (T)
BBL/(T)
Barrels per time unit (T)
BUSH/(T)
Bushels per time unit (T)
cuYD/(T)
Cubic Yards per time unit (T)
cuFt/(T)
Cubic Feet per time unit (T)
cuIn/(T)
Cubic Inches per time unit (T)
LiBBL/(T)
Liquid barrels per time unit (T)
BBBL/(T)
Beer barrels per time unit (T)
HECtL/(T)
Hectoliter per time unit (T)
AF/(T)
Acre-Foot per time unit (T)
CUSTOM/
Custom unit per time unit (T)
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Setting Custom Units (CUSTOM)
When the desired unit class or unit of measure within a class is not available, a custom unit may be programmed. Select the
CUSTOM menu (or CUSTOM unit within a unit class) to enter a custom unit name.
Text values are set using the Right and Up-Arrow buttons. Press Right-Arrow to select next character and
Up-Arrow to increment character value. The selected character will flash. Press and hold the Up or Right-Arrow
buttons to auto-increment or decrement the character. Press Enter to accept the character.
Notes:
• Press and hold the Right-Arrow while no character is being edited to erase all characters to the right of the
flashing character
• Press and hold Up or Right-Arrow to auto-increment or decrement a selected character.
• All text values, including tags and alarm messages, are set in a similar fashion.
Setting the Display Features (DISPLAY)
The meter’s display functions may be programmed using the Display menu. This menu consists of the
following submenus: Units, Decimal Point, Comma, Bargraph, Top, and Bottom.
Changing the Engineering Units (UNITS)
It is possible to change the engineering units within the selected unit class without the need to re-scale the meter.
When selecting a new unit from within the DISPLAY menu (e.g. changing from gallons (GAL) to liters (L)), the meter
will automatically convert the display values to display the new unit. Enter the UNITS menu, select a new unit of
measure from the list of predefined units, and press the Enter button. If entering a custom unit (CUSTOM), a custom
conversion factor will need to be entered.
Changing the Decimal Point (DEC.PT)
The decimal point may be set with up to seven decimal places or with no decimal point at all.
Pressing the Right-Arrow moves the decimal point one place to the right until no decimal point is displayed, and then
it moves to the left most position. Pressing the Up-Arrow moves the decimal point one place to the left.
If the dual-scale level feature is selected, the decimal point selections for PV1 & PV2 are enabled.
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Enabling or Disabling Commas on the Bottom Display (COMMA)
The bottom display is set to show a comma
separating the thousands and millions place by
default if a numeric value is being displayed. This
feature can be disabled or enabled using the Comma
menu.
Display Capabilities Optimization (TOP and BOTTOM)
Display Configuration Examples
The meter’s dual-line display can be setup in multiple
ways to provide an extremely informative view of the
process variable being monitored. The following
graphics show typical configurations:
Top Display: Process Variable
Bottom Display: Engineering Units or Tag
Top Display: Process Variable
Bottom Display: Toggling Between Units and Tag
Dual-Scale Mode:
Top Display: Toggling Between Process Variable and Units
Bottom Display: Toggling Between Process Variable
(in different scale) and Different Units
Note: To display units as GALLONS, select custom
units and enter the desired text.
Top Display: Toggling Between Process Variable and Units
Bottom Display: Percent
Top Display: Maximum Value
Bottom Display: Process Value
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Configuring the Display (TOp and BOTTOM)
The display is configured using the TOP and BOTTOM menus in the DISPLY menu. Additional menus are available if
the meter is in dual-scale mode to allow the second PV to be displayed on either the top or bottom display.
The top display (TOP) can display:
• Process Value (PV)
• Process Value 2 (dual-scale only; see PV 2
under advanced features menu)
• Alternating PV and Units
• Alternating PV and Tag
• Alternating PV, Units, and Tag
• Tag
• Stopwatch
• Open Collector 1 or 2 Timer
• Relay 1 or 2 Timer
• Minimum Value, Maximum Value, or Both
• Off (Blank)
• Units
The bottom display (BOTTOM) can display:
• Units
• Process Value (PV)
• Process Value 2 (dual-scale only; see PV 2
under advanced features menu)
• Alternating PV and Units
• Alternating PV and Tag
• Alternating Tag and Units
• Alternating PV, Units, and Tag
• Tag
• Stopwatch
• Open Collector 1 or 2 Timer
• Relay 1 or 2 Timer
• Off (Blank)
• PV’s Percentage of Full Scale
• The mA Input
• The mA Output
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Programming the Bargraph (BARGRAPH)
The meter comes equipped with a bargraph display for applications where a visual representation of the process
variable’s percentage of full scale is desirable. This feature can be enabled or disabled using the Bargraph menu
(BARGRAPH). The value displayed on the bargraph can be the percentage of full scale (PV PCT) or the percentage of
a user-programmable range (PV). If the meter is in dual-scale mode, the bargraph can be assigned to display either
PV1 or PV2 using this menu.
Programming the Outputs (OUTPUT)
All models come with two open collectors. Depending on the model purchased, the meter may include two solid-state
relays, and one 4-20 mA output. The Output menu will only show options for the available outputs. See Ordering
Information on page 11 for details.
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Open Collector Outputs
(OPEN COLLECTR)
The meter is equipped with two NPN open collector outputs as a standard feature that may be set up for pulse
outputs, alarms, timed pulses, or disabled.
Pulse outputs can be set to transmit the PV value (PV1 or PV2 if meter is in dual-scale mode). Output 2 may be used
to generate a quadrature output based on the other open collector output. An output test mode is also selectable to
generate pulses at a constant programmable frequency.
Alarms are available based on the PV value or the digital input. The alarm status will show on the display even if the
output is not wired.
A timer output (TIMER) turns the open collector on and off at the specified time intervals. The timer can be set as
single-shot or continuous timer.
The stopwatch output (STPWATCH) allows the open collector to be manually activated by starting the stopwatch. The
stopwatch count can be displayed on the top or bottom display.
The output may be disabled by selecting DISABLE.
The Open Collector Outputs are programmed in the following manner:
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Pulse Output (PULSE)
The pulse outputs may be programmed to generate a scaled frequency based on the PV and a programmable factor.
The factor determines the number of pulses per second generated per unit of measure. For example, if the meter
display shows 100 gallons and the factor is set to 2, the number of pulses generated per second would be 200. The
maximum frequency is 1,000 Hz.
Setting output 2 to quadrature will duplicate the other open collector output, but lag by 90 degrees out of phase. The
other output should be programmed as desired for the quadrature output function and must be a pulse (PULSE)
output selection. The quadrature maximum frequency for both outputs is 500 Hz.
The TEST option will output a fixed number of pulses per second based on the FREQ value entered.
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Alarm (ALARM)
Alarm outputs may be assigned to the PV or the digital input. When assigned to the PV, the alarm may be set as
either a high alarm or a low alarm. Alarm actions (AUTO, AUTO.MAN, LATCH, L-CLEAR) determine how and when the
alarm should be reset. They operate as follows:
• Automatic (AUTO): Alarm will reset automatically once the alarm condition has cleared.
• Automatic/Manual (AUTO.MAN): Alarm will reset automatically once the alarm condition has cleared but can
also be reset using the Enter (ACK) button (or whichever function key is set to acknowledge) at any time.
• Latching (LATCH): Alarm must be reset manually and can be done so at any time. Press the Enter (ACK)
button at any time to clear the alarm.
• Latching with Reset after Clear (L-CLEAR): Alarm must be reset manually and can only be done so after
the alarm condition has cleared. Press the Enter (ACK) button after the alarm condition has cleared to reset
the alarm.
If the alarm is set to PV, a set and reset point must be programmed. The set point is the display value at which the
alarm will turn on and the reset point is the display value at which the alarm will turn off. If the set point is lower than
the reset point, the alarm will be a low alarm; if the set point is higher than the reset point, the alarm will be a high
alarm. The digital input alarm will trigger whenever the digital input is triggered.
For both the PV and digital input alarms, a delay before the alarm is turned on or off may be set, as well as a fail-safe
feature which reverses the on/off operation of the open collectors.
Alarm states will be displayed on the meter even if no open collector output is physically connected. These may
include a red LED backlight, flashing PV value (PV alarm only), a programmable alarm message, an alarm indicator
, and flashing bargraph segment.
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Flashing Red Alarm (RED)
The last two lines in the preceding menu flow chart show how to program the display to turn red, flash, and display a
message when an alarm occurs.
Timer (TIMER)
The timer output may be set to generate the timed pulse only once (ONESHOT) or continuously (CONT).
The timer output produces a constant width pulse at a constant frequency, if set as continuous timer. Program the Off
Delay (OFF.DLAY) from 1 second to 99 hours 59 minutes and 59 seconds. This is the time it takes from selecting
START to turning on the output and for how long the output is off in continuous mode.
Program the On Time (ON TIME) for the active low pulse from 1 second to 99 hours 59 minutes and 59 seconds
(pulse width). This is the period of time for which the output will remain on.
Select Start (START) to begin outputting the constant timed pulse.
Select Stop (STOP) to end outputting the constant timed pulse.
Function keys or the digital input may be assigned to start and stop timer functions (see the USER menu in the
Advanced Menu).
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Stopwatch (STPWATCH)
The stopwatch function may be used to manually run and control a process for a specific time interval up to 99 hrs.,
59 min, and 59 seconds. The stopwatch function may be assigned to any open collector. There are three settings
needed to use the function effectively.
1. Assign stopwatch to either top or bottom display
2. Assign the open collector to control the
process (on/off)
3. Assign a function key or digital input to start/stop the stopwatch
Application Example
To maintain consistency of a product, it is necessary to take and test samples at different times throughout the day.
The stopwatch function is used to open and close a solenoid valve to know the exact amount of time needed to
complete the desired sample. Once this is determined, the timer function can be used to automatically take a sample
(batch) based on the time determined using the stopwatch function.
Setup: Assign the following to Stopwatch Function
• Bottom display
(see pages 36 & 38 for details how to change the display)
• Relay 1
(see pages 39 & 45 how to change Open Collector and Solid-State Relay functionality)
• F3: Start/Stop
(see pages 61 & 62 for details on how to change the function keys)
Procedure
• Press F3 to start the stopwatch; relay 1 turns on and the process starts running.
• Press F3 to stop the stopwatch; relay 1 turns off and the process stops.
• The bottom display indicates the time it took to complete the sample.
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Solid-State Relay Outputs (RELAY)
The meter can be optionally equipped with two solid-state relays that may be set up for alarms, timer, stopwatch, or
pump control. Alternatively, they may be disabled.
Alarms are available based on the PV value or the digital input. The alarm status will show on the display even if the
output is not wired.
Pump control allows the relay to turn on and off a pump at specified on and off points. This can be done using only
one of the relays to control one pump (ON-OFF) or using both relays in tandem to alternate between two pumps
(ALTERN).
A timer output (TIMER) turns the relay on and off at the specified time intervals. The timer can be set as single-shot
or continuous timer.
The stopwatch output (STPWATCH) allows the relay to be manually activated by starting the stopwatch. The
stopwatch count can be displayed on the top or bottom display.
The output may be disabled by selecting DISABLE.
• During setup, the relays do not follow the input and they will remain in the state found prior to entering the
Relay menu.
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Alarm (ALARM)
Alarm outputs may be assigned to the PV or the digital input. When assigned to the PV, the alarm may be set as
either a high alarm or a low alarm. Alarm actions (AUTO, AUTO.MAN, LATCH, L-CLEAR) determine how and when the
alarm should be reset. They operate as follows:
• Automatic (AUTO): Alarm will reset automatically once the alarm condition has cleared.
• Automatic/Manual (AUTO.MAN): Alarm will reset automatically once the alarm condition has cleared but can
also be reset using the Enter (ACK) button (or whichever function key is set to acknowledge) at any time.
• Latching (LATCH): Alarm must be reset manually and can be done so at any time. Press the
Enter (ACK) button at any time to clear the alarm.
• Latching with Reset after Clear (L-CLEAR): Alarm must be reset manually and can only be done so after
the alarm condition has cleared. Press the Enter (ACK) button after the alarm condition has cleared to reset
the alarm.
If the alarm is set to PV, a set and reset point must be programmed. The set point is the display value at which the
alarm will turn on and the reset point is the display value at which the alarm will turn off. If the set point is lower than
the reset point, the alarm will be a low alarm; if the set point is higher than the reset point, the alarm will be a high
alarm. The digital input alarm will trigger whenever the digital input is triggered.
For both the PV and digital input alarms, a delay before the alarm is turned on or off may be set, as well as a fail-safe
feature which reverses the on/off operation of the relays.
Alarm states will be displayed on the meter even if no relay output is physically connected. These may include a red
LED backlight, flashing PV value (PV alarm only), and a programmable alarm message. In addition, for meters
without a bargraph an alarm indicator (!) (only on meters with no bargraph) will also display.
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Pump Control (PUMPCTRL)
The pump control output is used in situations where the relays are used to control pumps. There are two options
available for controlling pumps: on-off (ON-OFF) and pump alternation (ALTERN).
ON-OFF will turn the relay on at a programmed on point and off at a programmed off point. Setting the on point higher
than the off point will make the output activate on a high PV value; setting the on point lower than the off point will
make the output activate on a low PV value. The relay will reset automatically.
For pump control applications where two similar pumps are used to control the level of a tank or a well, it may be
desirable to have the pumps operate alternately. This prevents excessive wear and overheating of one pump over the
lack of use of the other pump. Pump alternation uses both relays in tandem to alternate between two similar pumps.
The ALTERN menu is only available under Output 1 and will automatically set Output 2 to pump alternation as well.
Use the pump Alternation Time setting (ALT.TIME) to control the alternation based on runtime in addition to level
cycles.
On/Off Pump Control (ON-OFF)
When programming a single pump to turn on and off, the on and off points must be programmed. The relay will
activate at the on point and deactivate at the off point. On and off delays may be programmed to delay the activation
or deactivation of the relay by a certain number of seconds after reaching either the on point or off point.
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Pump Alternation (ALTERN)
Pump alternation sets the two relays to alternate every time the first on point (ON 1) is reached. The active relay will
turn off once the first off point (OFF 1) is reached. If the PV reaches the second on point (ON 2), the other relay will
also turn on. The second relay will turn off once the second off point (OFF 2) is reached and the first relay will remain
active until the first off point (OFF 1) is reached.
On and off delays may optionally be programmed for each on and off point to delay the activation or deactivation of
the relays by a certain number of seconds after reaching either the on point or off point.
For pumps that typically remain on extensively, the alternation time (ALT.TIME) parameter sets a period of relay ontime after which the relays should alternate. For example, if the alternation time is set to one hour, pump 1 will turn off
after one hour of runtime regardless of the level reading, at which point pump 2 becomes the active pump. Pump 2
will run until one hour has passed, or the tank has reached a desirable level; whichever happens first. By using the
proper on/off points, the alternation can be set up so that the first pump on is the first pump off. This is desirable when
the two pumps are of similar rating.
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Pump Control with Alternation & Alarm Example
The following is a typical application where the relays and open collectors are used for pump alternation and high and
low level alarm.
Pump and Alarm On & Off Point Programming
Relay
On Point
Off Point
Function
OC
On Point
Off Point
Function
1
7000
2000
Controls backup pump
1 7000
6500
Trips high alarm
2
6000
2000
Controls main pump
2 1000
1500
Trips low alarm
The following graphics provide a visual representation of a typical pump alternation application:
Relay #2 turns the main pump on at 6000 gallons and
turns it off at 2000 gallons. lights up to show relay 2
is energized. The indicates level is rising.
With the Pump Alternation feature activated, the next time
the level reaches 6000 gallons, relay #1 transfers and
starts the backup pump. lights up to show relay 1 is on.
If the backup pump is not able to keep up, and the
level reaches 7000 gallons, relay #2 transfers and
starts the main pump as well. Open collector #1 trips
the High Level Alarm, the display turns red and flashes
“Hi Level” message, and indicates an alarm
condition. The High Level Alarm resets at 6500
gallons.
Once the level has dropped below the reset points, both
relays will turn off. If the Main Pump fails to turn off, open
collector #2 trips the Low Level Alarm at 1000 gallons to
warn against the pump running dry. The Low Level Alarm
resets at 1500 gallons.
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Timer (TIMER)
The timer output may be set to generate the timed pulse only once (ONESHOT) or continuously (CONT). The timer
output produces a constant width pulse at a constant frequency, if set as continuous timer.
Program the Off Delay (OFF.DLAY) from 1 second to 99 hours 59 minutes and 59 seconds. This is the time it takes
from selecting START to turning on the output and for how long the output is off in continuous mode.
Program the On Time (ONTIME) for the active low pulse from 1 second to 99 hours 59 minutes and 59 seconds
(pulse width). This is the period of time for which the output will remain on.
Select Start (START) to begin outputting the constant timed pulse. Select Stop (STOP) to end outputting the constant
timed pulse. Function keys or the digital input may be assigned to start and stop timer functions (see the USER menu
in Advanced).
Stopwatch (STPWATCH)
The stopwatch function may be used to manually run and control a process for a specific time interval up to 99 hrs.,
59 min, and 59 seconds. The stopwatch function may be assigned to any relay. There are three settings needed to
use the function effectively.
1. Assign stopwatch to either top or bottom display
2. Assign the relay to control the process (on/off)
3. Assign a function key or digital input to start/stop the stopwatch
Application Example
To maintain consistency of a product, it is necessary to take and test samples at different times throughout the day.
The stopwatch function is used to open and close a solenoid valve to know the exact amount of time needed to
complete the desired sample. Once this is determined, the timer function can be used to automatically take a sample
(batch) based on the time determined using the stopwatch function.
Setup: Assign the following to Stopwatch Function
• Bottom display
(see pages 36 & 38 for details how to change the display)
• Relay 1
(see pages 39 & 45 how to change Open Collector and Solid-State Relay functionality)
• F3: Start/Stop
(see pages 61 & 62 for details on how to change the function keys)
Procedure
• Press F3 to start the stopwatch; relay 1 turns on and the process starts running.
• Press F3 to stop the stopwatch; relay 1 turns off and the process stops.
• The bottom display indicates the time it took to complete the sample.
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Runtime & Cycle Count (INFO)
The relay information menu shows runtime and cycle count for each relay. These values may be cleared at any time
by selecting the Clear option (CLEAR?).
Isolated 4-20 mA Output (4-20 mA)
The 4-20 mA menu is used to scale the isolated 4-20 mA output based on display values. This menu is not present
on models without a 4-20 mA output option.
The 4-20 mA analog output can be scaled to provide a 4-20 mA signal for any PV display range or to simply
retransmit the 4-20 mA input. The output may be disabled (DISABLE), and will only output the minimum signal.
Overrange and underrange values determine what mA signal the meter will output if the mA input is underrange
(<3.5 mA) or overrange (>20.5 mA). This value may be set to 1 mA, 3.5 mA, 3.8 mA, 20.5 mA, 20.8 mA, 23 mA, or
disabled.
No equipment is needed to scale the analog output; simply program two display values and corresponding mA output
signals.
Process Variable (PV)
To scale the analog output, enter display value 1 and a corresponding analog output value for this display, and enter
display value 2 and a corresponding analog output value for this display value. This will provide a scaled linear
analog output.
Retransmit (RETRANS)
This option will retransmit the 4-20 mA analog input without the need to scale the output.
Output Manual Control (CONTROL)
The Control menu is used to control the open collector outputs, 4-20 mA analog output, and the relays manually,
ignoring the input. Each open collector, relay, and analog output can be programmed independently for manual
control. Selecting automatic control sets all relays and analog output for automatic operation.
After selecting manual control for a specific output, you can set the output value. To change the output value, return
to the Control menu, select the output to control, select manual control, and enter a new value.
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Advanced Features Menu (ADVANCE)
To simplify the setup process, functions not needed for most applications are located in the Advanced Features
menu. The options under advanced features include advanced PV setup, cutoff, filter, password, function key
programming, and system settings.
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Advanced Process Variable Setup (ADV PV SETUP)
The Advanced PV Setup menu contains options to apply input signal conditioning functions to the input and to
scale/calibrate the input signal.
Input Signal Conditioning Functions (FUNCTN)
The Function menu is used to select the input signal conditioner applied to the input: linear, square root,
programmable exponent, or round horizontal tank volume calculation. Multi-point linearization is part of the linear
function selection.
Meters are set up at the factory for linear function with 2-point linearization. The linear function provides a display that
is linear with respect to the input signal.
Using MeterView XL
MeterView XL makes programming the input signal conditioning functions quick and easy. Go to the input/scale menu
and select the desired function from the drop down menu in the “scale input” section.
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Square Root Linearization (SQROOT)
The square root function can be used to linearize the signal from a differential pressure transmitter and display flow
rate in engineering units.
PD6908 Displaying Flow Rate by Applying the Square Root Function to the Output of a DP Transmitter.
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Programmable Exponent Linearization (EXPONEN)
The programmable exponent can be used to linearize the signal from level transmitters in open-channel flow
applications using weirs and flumes.
The PD6908, in combination with an ultrasonic level transmitter, makes for an economical way to measure and
display open channel flow rate in most weirs and flumes. A guide such as the ISCO Open Channel Flow
Measurement Handbook can provide the user with all the information needed: the exponent used in the flow equation
for the desired flow units and the flow rate for any given head height. For example, to display the open channel flow
rate from a 3" Parshall flume, the ISCO handbook advises the exponent is 1.547 and at the maximum head height of
3.0 feet, the flow rate is 3.508 MGD.
3" Parshall Flume Discharge Table
Formula: CFS = 0.9920 H
1.547
GPM = 445.2 H
1.547
MGD = 0.6411 H
1.547
Where: H = Head in feet
Table 12-3
Head
(Feet)
CFS
GPM
MGD
3.00
5.428
2436
3.508
ISCO Open Channel Flow Measurement Handbook, 3rd edition
With this information the PD6908 should be programmed in the following fashion. This setup assumes the level
transmitter is programmed to output 20 mA at the maximum head height of 3.00 feet; but any mA value at a head
height with a known flow rate may be used.
Function
Desired
Programming
Open Channel Flow
3" Parshall flume
Set Programmable Exponent to 1.547
Flow Rate
Millions of Gallons per
Day (MGD)
Set 4 mA = 0
20 mA = 3.508
Display
Display Flow Rate
Set upper display for flow rate display and lower display
units/tag for MGD.
To display both flow rate and total, consider Precision Digital’s Model PD6928 Flow Rate Totalizer.
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The Programmable Exponent function is programmed in the following manner:
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Multi-Point Linearization (LINEAR)
Up to 32 linearization points can be selected for PV1 and
PV2 under the LINEAR function. Multi-point linearization
can be used to linearize the input so the meter can display
volume from non-linear tanks or to convert level to flow
using weirs and flumes with complex equations. These
points are established via direct entry (SCALE) or with a
live calibration signal source (CAL).
If the dual-scale level feature has been selected, the
menus for PV1 & PV2 are enabled.
MeterView XL showing the
linear points setup feature. Up
to 32 points can be selected
for PV1 and PV2.
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Round Horizontal Tank Linearization (RH TANK)
This function automatically calculates the volume in a round horizontal tank with flat ends. It is only available for PV2
while the meter is in dual-scale mode.
Set the display for the desired decimal point and engineering units before entering the round horizontal tank function.
Select units (inches or cm) for the tank dimensions. Enter the diameter and the length in inches or cm and the results
will be calculated automatically in US gallons or liters. The unit of measure for the volume can be changed using the
display menu. See Changing the Engineering Units (UNITS) on page 36 and Available Unit Classes and Units on
page 35 for a list of available volume units. There is no need to enter scaling values.
MeterView XL Round Horizontal Tank Function Automatically Calculates the Volume Once the Diameter and the Length of
the Tank are Entered.
PD6908 Displaying Height in Feet and Volume in Gallons in a Round Horizontal Tank
Using the Round Horizontal Tank Linearization Feature.
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Advanced Scaling and Calibration (SCALE.CAL)
This menu offers options to scale or calibrate the meter.
Scaling the Input (SCALE)
The scale menu in the Advanced menu is the same as the scale menu in the Input menu. See Scaling the 4-20 mA
Input (INPUT) on page 34 for details about scaling the meter.
Calibrating the Input (CAL)
To scale the meter without a signal source, refer to
Scaling the 4-20 mA Input (INPUT) on page 34.
The meter can be calibrated to display the process in engineering units by applying the appropriate input signal and
following the calibration procedure. The CAL menu can be used either with a calibrated current source or with a live
signal coming from a 4-20 mA transmitter connected to the process being measured.
During calibration, the mA input value will be displayed as INP 1 and INP 2. Adjust the input source until the
desired mA value is shown.
The use of a calibrated signal source is required.
Follow these steps to calibrate the input:
1. After accessing the SCALE.CAL menu, press the Right-Arrow button to scroll to the Calibration menu (CAL
PV) and press Enter.
2. Select the appropriate units for the desired process variable, then press Enter. For information on units, see
Available Unit Classes and Units on page 35.
3. The meter displays INP 1. Apply a known signal and press Enter. The display will flash while accepting the
signal.
4. After the signal is accepted, the meter displays DSP 1. Enter a corresponding display value for the input
signal, and press Enter to accept.
5. The meter displays INP 2. Apply a known signal and press Enter. The display will flash while accepting the
signal.
6. After the signal is accepted, the meter displays DSP 2. Enter a corresponding display value for the input signal
and press Enter to accept.
7. After completing calibration, the SAVE? display will need to be acknowledged using the Enter key before
calibration will take effect.
Note: The SAVE? prompt is not displayed if no changes have been made to the scaling.
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Low-Flow Cutoff (CUTOFF)
The low-flow cutoff feature allows the meter to be programmed so that the often-unsteady output from a differential
pressure transmitter at low flow rates always displays zero on the meter. The cutoff value may be programmed from
0.1 to 99999. The meter will display zero below the cutoff value. The cutoff can be disabled to display negative
values.
Noise Filter (FILTER)
The noise filter is available for unusually noisy signals that cause an unstable process variable display. The noise
filter averages the input signal over a certain period of time. The filter level determines the length of time over which
the signal is averaged. The filter level can be set between 1 and 16 seconds or turned off. The higher the filter level,
the longer the averaging time and so the longer it takes the display to settle to its final value. Setting the filter level to
off disables the filter function.
Noise Filter Bypass (BYPAS)
The noise filter bypass changes the behavior of the meter so that small variations in the signal are filtered out but
large abrupt changes in the input signal are displayed immediately. The bypass value determines the minimum
amount of signal change to be displayed immediately. All signal changes smaller than the bypass value are filtered or
averaged by the meter. The noise filter bypass may be set between 0.1 and 99.9% of full scale.
Enabling Password Protection (PASSWRD)
The Password menu is used for programming security to prevent unauthorized changes to the programmed
parameter settings.
To set a password, enter the Password menu and program a five-digit password. When a password has been
enabled, the lock icon will display in the upper-left side of the display. For instructions on how to program numeric
values see Setting Numeric Values on page 33.
Making Changes to a Password Protected Meter
If the meter is password protected, the meter will display the message LOCKED when the Menu button is pressed.
Press the Enter button while the message is being displayed and enter the correct password to gain access to the
menu. After exiting Programming Mode, the meter returns to its password protected condition.
Disabling Password Protection
To disable password protection, access the Password menu and clear the entered password either by pressing and
holding the Right Arrow button until all digits reset to zero or manually changing all the digits to zero. When the Enter
button is pressed, the meter will display UNLOCKD and will no longer require a password to access Programming
Mode.
Note: If the meter is password protected and the password has been forgotten, the password may be overridden
using the master password: 50865
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Programmable Function Keys User Menu (USER)
The User menu allows the user to assign the CapTouch buttons function keys F1, F2, and F3, and the digital input
(located on the input signal connector) to access some of the menus or to activate certain functions immediately (e.g.
reset max & min, hold relay states, etc.). This allows the meter to be greatly customized for use in specialized
applications.
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Function Keys & Digital Input Available Settings
Refer to the following table for descriptions of each
available function key or digital input setting.
Display
Description
DISP FN
Set the function key or digital input to
display a value
DISPLAY
Cycle max, min, and PV(s)
DISP PV
Display the PV
PCT PV
Display the PV’s percentage of max
(20 mA)
D UNITS
Display the PV’s units
D TAG
Display the PV’s tag
DISPMIN
Display the PV’s minimum
DISPMAX
Display the PV’s maximum
MIN MAX
Display the PV’s minimum and
maximum value
D mA IN
Display the mA input value
D mAOUT
Display the mA output value
MENU FN
Set the function key or digital input to
access a menu
RLYINFO
Go to relay information menu (INFO)
MANCTRL
Go to output control menu
(CONTROL)
TIMR OC1
Open collector 1 timer
TIMR OC2
Open collector 2 timer
TIMER R1
Relay 1 timer
TIMER R2
Relay 2 timer
TIMER.FN
Set the function key or digital input to
start or stop a timer
STRT.ALL
Start all timers
STOP.ALL
Stop all timers
S.STP.ALL
Start or stop all timers
OC1
Start/stop open collector 1 timer
OC2
Start/stop open collector 2 timer
RLY1
Start/stop relay 1 timer
RLY2
Start/stop relay 2 timer
START
Start the selected timer output
STOP
Stop the selected timer output
STR-STP
Start or stop the selected timer
output
ALARM.FN
Set the function key or digital input to
acknowledge an alarm
ACK
Acknowledge all active alarms
SETPOINT
Set all output set point
SETPT.OC1
Set open collector 1 set point
SETPT.OC2
Set open collector 2 set point
SETPT.R1
Set relay 1 set point
SETPT.R2
Set relay 2 set point
SWATCH.FN
Set the function key or digital input to
activate stopwatch
Display
Description
START
Start the stopwatch
STOP
Pause/Stop the stopwatch
STR-STP
Start or stop the stopwatch
TARE.FN
Set the function key or digital input to
tare the display value
TARE
Tare the display value
RST TARE
Reset the display value
HOLD FN
Set the function key or digital input to
hold an output
HOLD.OUT
Hold all outputs
HLD.UNHLD
Hold or un-hold all outputs
OC1+2
Hold/un-hold open collector outputs
RLY1+2
Hold/un-hold relay outputs
mAOUT
Hold/un-hold 4-20 mA output
HOLD
Hold selected output
HLD.UNHLD
Hold or un-hold selected output
DISABLE
Disable the function key or digital
input
RST FN
Set the function key or digital input to
reset a value
RESET
Reset min, max, or max/min PV
value
R MIN.MAX
Reset max and min PV value
Enabling the Function Key Hint Feature (HINT)
Enabling the function key hint feature will cause a hint
message to be displayed when pressing the F1, F2,
or F3 function keys. This text gives a brief description
of what the button is programmed to do. Pressing that
function key a second time will execute that action.
The hint feature does not affect the digital input (DI)
which is intended for immediate execution.
Tare (TARE)
The tare function zero’s out the display. In the case of
scale weight, tare is used to eliminate container
weight and provide net weight readings. There are
two tare functions; Tare and Reset Tare. When the
tare function is used, the display reading is offset by
the displayed amount to make the displayed value
zero. Reset tare removes the display offset of the net
value, and the gross and net values become the
same until a new capture tare is entered.
Program a function key or the digital input for the tare
and reset tare.
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Changing System Settings (SYSTEM)
The System menu contains the following menus:
Analog Output Calibration, Restore Factory Defaults,
Dual-Scale (PV2), Backlight, CapTouch Buttons
Operation Mode, Information, and Internal Calibration.
Note: The Analog Output Calibration menu is
available only if the option is installed.
Analog Output Calibration (AOUTCAL)
To perform the analog output calibration, it is
recommended to use a milliamp meter with a
resolution of at least 0.1 µA to measure the output
current. The values saved internally during this
procedure are used for scaling the 4-20 mA output in
the Setup menu.
4-20 mA Output Calibration Procedure
1. Go to the Advanced Features menu and
navigate to the SYSTEM menu and press
Enter. Navigate to AOUTCAL and press Enter.
2. The display will show 4 mA. The ProtEX+ mA
output should now be close to 4 mA. Enter the
actual value read by the digital mA meter on
the bottom display and press Enter.
3. The display will show 20 mA. The ProtEX+ mA
output should now be close to 20 mA. Enter
the actual value read by the digital mA meter
on the bottom display and press Enter.
4. The ProtEX+ will now calculate the calibration
factors and store them.
5. Press Menu to exit.
Enabling the Dual-Scale Feature (PV2)
Dual-Scale Mode
Top Display: Toggling Between Process Variable and Units
Bottom Display: Toggling Between Process Variable
(in different scale) and Different Units
For some level applications, such as displaying the
height and volume of a tank, a second PV can be
enabled which can be scaled to display a different
value based on the same 4-20 mA input. This is
accomplished by enabling the dual-scale feature
(PV2).
When the dual-scale feature is enabled, additional
menus will be displayed to allow for the programming
of the second PV. The input menu will display PV1
and PV2 for scaling and the display menu will allow
both PVs to be displayed on either top or bottom
display, for example. See Display Functions &
Messages on page 28 for additional information on
where additional dual-scale specific menus will
appear.
PV2 must be enabled to use the Round Horizontal
Tank feature. See Round Horizontal Tank
Linearization (RH TANK) on page 58.
For instructions on how to enable PV2 see Changing
System Settings (SYSTEM) on page 63.
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Enabling or Disabling the Backlight (BACKLITE)
The backlight may be enabled or disabled using the
System - Backlight menu. The backlight is enabled by
default, but the input must be wired appropriately for
the backlight to function. See Wiring Diagrams on
page 23.
CapTouch Buttons Operation Mode (CAPTOUCH)
CapTouch buttons have two modes of operation:
Normal and Delayed. Delayed mode prevents
accidental trigger of the buttons. In the Delayed
mode, the buttons enter into a low sensitivity state
(sleep) and they ignore quick button presses after 20
seconds of inactivity. To wake up the buttons, press
and hold any button for more than 2 seconds, the
buttons respond normally.
Viewing System Information (INFO)
System information, such as software (firmware)
number and version, model number, and system tag,
may be viewed in the INFO menu. Press the Right
Arrow button to cycle through all available meter
information. Press Menu to go back to the previous
menu.
Calibrating the Internal mA Reference (ICAL)
The meter is factory calibrated prior to shipment to display
0.00 to 100.00, which corresponds to the 4-20 mA input.
The calibration equipment is traceable to NIST standards.
The use of calibrated signal sources is necessary to
calibrate the internal source of the meter. The meter’s
internal source is what allows the user to scale the
meter without applying a signal.
Check calibration of the meter at least every
12 months.
Note: Allow the meter to warm up for at least
15 minutes before performing the internal source
calibration procedure.
The Internal Calibration menu is part of the Advanced
menu. Internal Calibration is performed as follows:
1. Press the Menu button to enter
Programming Mode.
2. Press the Up-Arrow button twice and press
Enter to access the Advanced menu.
3. Press the Up-Arrow button and press Enter
to access the System menu.
4. Press the Up-Arrow button and press Enter
to access the ICAL menu.
5. The meter displays low input current
message
(4.000 mA). Apply a 4 mA signal and press
Enter. The display flashes for a moment
while the meter is accepting the low input
signal.
6. After the display stops flashing, the display
moves to the high input calibration (20.000
mA). Apply the high input signal and press
Enter. The display will flash again while the
meter is accepting the high input signal.
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PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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Meter Operation
The meter is equipped with four CapTouch throughglass buttons. These buttons allow meter operation
without removing the cover and exposing the
electronics in a hazardous area.
Three CapTouch buttons labeled F1, F2, and F3 can
be programmed as function keys to perform a variety
of meter functions simply by pressing on the glass
over the button. These include operation of the tare
function, resetting the tare, resetting the meter’s
relays or open collectors, starting and stopping timers,
and displaying max/min values. See Function Keys &
Digital Input Available Settings on page 62 for a
complete list of settings available.
A digital input is available on the meter and it may
function in a similar fashion as the function keys to
allow remote operation of a single task.
The max & min readings (peak & valley) reached by
the process can be displayed either continuously by
assigning it to a display line in the Display menu, or
momentarily by pressing the F1 key (default) or
assign it to any of the other function key or the digital
input.
Pressing the F1 key cycles through various display
values (e.g. max, min); press the Enter key to lock the
display in the current process value and press the
Enter key again to unlock the display.
The relay information menu shows runtime and cycle
count for each relay.
Change the display units within the selected unit class
at any time without the need to re-scale the meter.
Select the desired units via the UNITS menu in the
DISPLAY menu, and the meter automatically converts
the display values to the new unit of measure.
CapTouch Buttons Operation
Button
Description
(Default Settings)
Press to enter or exit Programming
Mode, view settings, or exit max/min
readings
Press to display max/min readings.
Press to reset max/min readings.
Press to acknowledge all manually
resettable relays or open collectors.
Press to lock/unlock the display value
after pressing the F1 key.
CapTouch Buttons
The PD6908 is equipped with four capacitive sensors
that operate as through-glass buttons so that it can be
programmed and operated without removing the
cover (and exposing the electronics) in a hazardous
area.
These buttons can be disabled for security by
selecting the Lock setting on the switch located on the
side of the display module, close to the Menu button.
To actuate a button, press one finger to the glass
directly over the marked button area. When the cover
is removed, the CapTouch buttons can be used after
the meter completes a self-calibrating routine (hand
symbol flashes). The sensors are disabled when more
than one button is pressed, and they will automatically
re-enable after a few seconds (hand symbol off).
CapTouch Button Tips & Troubleshooting
The CapTouch buttons are designed to work under
any lighting condition and to protect against false
triggering. If the CapTouch buttons are not needed
during operation, they can be disabled (slide switch to
Lock).
• To remove cover with power applied (safe area
only), or to clean the window, place your hand
over the buttons; this will temporarily disable the
CapTouch buttons to prevent inadvertent use.
• Keep the glass window clean.
• Tighten the cover securely.
• Use a password to prevent tampering.
• CapTouch buttons will not work if two or more
buttons are detected as being pressed
simultaneously. Be careful to avoid triggering
multiple buttons or reaching across one button
location to press another.
Page 66
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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66
Function Keys Operation
During operation, the programmable function keys
operate according to the way they have been
programmed in the Advanced Features – User menu.
The table under CapTouch Buttons Operation on
page 65 shows the factory default settings for F1, F2,
and F3.
A hint message may be enabled to provide a
description of what each function key does prior to
executing their assigned function. See Enabling the
Function Key Hint Feature (HINT) on page 62.
Digital Input Operation
A digital input is standard on the meter. This digital
input is programmed identically to function keys F1,
F2, and F3. The input is triggered with a contact
closure between DI+ and DI-, or with an active low
signal. During operation, the digital input operates
according to the way it has been programmed in the
Advanced Features – User menu.
Maximum/Minimum Readings
The max & min readings (peak & valley) reached by
the process can be displayed either continuously or
momentarily.
Display momentarily by pressing the F1 function key
(default) or assigning to any of the other function keys
or to the digital input in the User menu.
Display continuously by pressing the Enter button
while the max/min is being displayed to lock the
display. Press Enter again to unlock.
Any of the F1-F3 function keys (buttons) and the
digital input can be programmed to reset the max &
min readings. The meters are set at the factory to
display the max reading by pressing the Right
Arrow/F1 button and to use the Up-Arrow/F2 button to
access the Reset menu. Press the Right Arrow button
to cycle through the available parameters to reset.
Top Display: Process Value
Bottom Display: Max & Min
Runtime & Cycle Count (INFO)
The relay information menu shows runtime and cycle
count for each relay. These values may be cleared at
any time by selecting the Clear option (CLEAR?). If
the cycle count or runtime values need to be changed
on a frequent basis, it would be convenient to set up a
CapTouch button or the digital input to simplify this
process.
Note: See the menu tree under Solid-State Relay
Outputs (RELAY) on page 45 for complete menu
structure on this feature.
Meter displaying the
amount of time a relay
has been activated
Meter displaying the
number of times a relay
has cycled
Changing Engineering Units
During operation of the meter, it is possible to change
the display units within the selected unit class without
the need to re-scale the meter. The UNITS menu in the
DISPLAY menu allows the unit of measure to be
changed (e.g. from gallons/second (GAL/s) to
liters/second (L/s)) and the meter will automatically
convert the display values to the new unit of measure.
If entering a custom unit (CUSTOM), a custom
conversion factor will need to be entered. See
Changing the Engineering Units (UNITS) on page 36.
Page 67
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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Troubleshooting
This product is a highly sophisticated instrument with
an extensive list of features and capabilities. If the
CapTouch buttons are used to program the meter, it
can be a difficult task to keep everything straight. That
is why we strongly recommend the use of the free
MeterView XL software for all programming activities.
A cable is provided to use the MeterView XL software
for programming the meter.
If you have programmed the meter with the CapTouch
buttons and it is not working as intended, try
re-programming the meter using the MeterView XL
software.
Reset Meter to Factory Defaults
When the parameters have been changed in a way
that is difficult to determine what’s happening, it might
be better to start the setup process from the factory
defaults. This can be accomplished using MeterView
XL software or with the CapTouch buttons.
To load factory defaults:
1. Press the Menu button to enter
Programming Mode.
2. Press the Right-Arrow button twice and
press Enter to access the Advanced menu.
3. Press the Up-Arrow button and press Enter
to access the System menu.
4. Press the Right-Arrow button and press
Enter to access the Default menu.
5. Press Enter twice in quick succession. The
meter will load default settings and restart.
Determining Software Version
To determine the software (firmware) version of a
meter:
1. Press the Menu button to enter
Programming Mode.
2. Press the Up-Arrow button twice and press
Enter to access the Advanced menu.
3. Press the Up-Arrow button and press Enter
to access the System menu.
4. Press the Up-Arrow button twice and press
Enter to access the Info menu.
5. Press the Right-Arrow button to cycle
through the meter information. When done,
press the Menu button to return to the
previous menu or press & hold Menu to exit
to Run mode.
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PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
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Factory Default Settings
The following table shows the factory setting for most
of the programmable parameters on the meter.
Parameter
Display
Default Setting
Input Menu
Unit Class
UNITS
Volume
Unit of Measure
UNIT
Gallons
Input 1
INP 1
4.000 mA
Display 1
DSP 1
0.00
Input 2
INP 2
20.000 mA
Display 2
DSP 2
100.00
Output Menu
Open Collector
Output 1
OUTPUT 1
Disabled
Pulse Factor
FACTOR
1.0
Test Frequency
FREQ
100
Alarm
ALARM
PV
Alarm Action
ACTION
AUTO
Set Point
SET
20.00
Reset Point
RESET
10.00
Alarm On Delay
DELAY ON
0 seconds
Alarm Off Delay
DELAY OFF
0 seconds
Alarm Fail-safe
FAILSAFE
OFF
Red LED
RED
ON
Flash PV
FLASH
ON
Alarm Message
MSG
ON
Message Text
MSG EDIT
ALARM 1
Timer Off Delay
OFF.DLAY
1 minute
Timer On Time
ON TIME
1 second
Timer Mode
MODE
Continuous
Open Collector
Output 2
OUTPUT 2
Disabled
Set Point
SET
40.00
Reset Point
RESET
30.00
Message Text
MSG EDIT
ALARM 2
Relay Output 1
RELAY 1
Disabled
Alarm
ALARM
PV
Alarm Action
ACTION
AUTO
Set Point
SET
70.00
Reset Point
RESET
60.00
Alarm On Delay
DELAY ON
0 seconds
Alarm Off Delay
DELAY OFF
0 seconds
Alarm Fail-safe
FAILSAFE
OFF
Red LED
RED
ON
Flash PV
FLASH
ON
Alarm Message
MSG
ON
Message Text
MSG EDIT
ALARM 3
Parameter
Display
Default Setting
Pump Control Menu
Pump Ctrl On
ON
70.00
Pump Ctrl Off
OFF
60.00
Pump Ctrl On
Delay
DELAY ON
0 seconds
Pump Ctrl Off
Delay
DELAY OFF
0 seconds
Pump Alt On 1
ON 1
70.00
Pump Alt Off 1
OFF 1
60.00
Pump Alt On 2
ON 2
90.00
Pump Alt Off 2
OFF 2
80.00
Pump Alt
On Delay 1
DELAY 1 ON
0 seconds
Pump Alt
Off Delay 1
DELAY 1 OFF
0 seconds
Pump Alt
On Delay 2
DELAY 2 ON
0 seconds
Pump Alt
Off Delay 2
DELAY 2 OFF
0 seconds
Timer Off Delay
OFF.DLAY
1 minute
Timer On Time
ON TIME
1 second
Timer Mode
MODE
Continuous
Relay Output 2
RELAY 2
Disabled
4-20 mA Output
4-20 mA
PV
Advanced Menu
Signal
Conditioning
Function
FUNCTN
Linear (2 pts)
Low Cutoff
CUTOFF
Enabled: 0
Filter
FILTER
2.0 seconds
Filter Bypass
BYPAS
0.4 PCT
Password
PASSWRD
00000
(Unlocked)
Function Key 1
F1
Display
Function Key 2
F2
Reset
Function Key 3
F3
Acknowledge
Digital Input
DI
Acknowledge
Hint Feature
HINT
Disabled
Dual-Scale
PV 2
Disabled
Backlight
BACKLITE
Enabled
CapTouch
CAPTOUCH
Normal
Display Menu
Unit of Measure
UNITS
Gallons
Decimal Point
Location
DEC.PT
2
Comma
COMMA
Enabled
Top Display
TOP
PV
Bottom Display
BOTTOM
Units
Page 69
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
Instruction Manual
69
Troubleshooting Tips
Certain sequences of events can cause unexpected results. To solve these issues, it is best to start fresh from factory defaults and
use the manual as a step by step programming guide, rather than a random approach to programming. To reset the meter to factory
defaults, see Factory Default Settings on page 68. In addition, for best results, we recommend using the free MeterView XL software
for all programming needs.
Symptom
Check/Action
No display at all
Check:
1. The 4-20 mA current loop is providing at least 3.5 mA to the meter.
2. The voltage drop of all devices connected to the 4-20 mA current loop does not
exceed the max rating of the loop power supply.
Not able to change setup or
programming, LOCKED is
displayed
Meter is password-protected. Enter correct five-digit password to unlock or Master
Password of 50865.
Meter display flashes:
1. 99999
2. -9999
Check that the number of digits required for the scaled value does not exceed the
maximum digits for the display. If it does, try adjusting the decimal point location for less
precision or changing the PV display to the bottom display.
Display is unstable
Check:
1. Input signal stability and value.
2. Display scaling vs. input signal.
3. Filter and bypass values (increase).
Display response is too slow
Check filter and bypass values
Display reading is not accurate
Check:
1. Input signal conditioner selected: Linear, square root, etc.
2. Scaling or calibration
Display does not respond to input
changes, reading a fixed number
Check display assignment. It might be displaying max, min, or set point.
Display shows:
1. MAX and a number
2. MIN and a number
Press Menu to exit max/min display readings.
Relay operation is reversed
Check fail-safe settings in Output menu
Relays do not respond to signal
Check:
1. Relay action in Output menu
2. Set and reset points
3. Check manual control menu
If the display locks up or the meter
does not respond at all
Cycle the power to reboot the microprocessor.
CapTouch buttons do not respond
1. If hand-symbol is flashing, multiple buttons were touch at the same time, wait a few
seconds until the hand symbol goes off.
2. If Delayed mode has been set, press & hold any button for 5 seconds, the buttons
should respond normally.
3. If the slide switch on the display module is in the Lock position, move the switch to
the Unlock position; see Disabling the CapTouch Buttons on page 25.
Other symptoms not described
above
Call Technical Support for assistance.
Page 70
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
Instruction Manual
70
Notes
Page 71
]
Page 72
PD6908 Explosion-Proof & Intrinsically Safe Loop-Powered Process Meter
Instruction Manual
PRECISION DIGITAL CORPORATION
233 South Street • Hopkinton MA 01748 USA
Tel (800) 343-1001 • Fax (508) 655-8990
www.predig.com
LIM6908HA_A
SFT125 Ver 1.000 & up
11/22
Contact Precision Digital
Technical Support
Call: (800) 610-5239 or (508) 655-7300
Fax: (508) 655-8990
Email: [email protected]
Sales Support
Call: (800) 343-1001 or (508) 655-7300
Fax: (508) 655-8990
Email: [email protected]
Place Orders
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For the latest version of this manual please visit
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