Red Lion PAXLCL User Manual

1

2

3

4

5

6

7

8

9

10

11

3.60 (91.4)

(44.5)

1.75

(96.5)

3.80

1.95

(49.5)

(2.5)

.10

(104.1)

4.10

(44.5)

1.75

1.8.8.8

mA

Tel [phone]

C

US LISTED

Fax [phone]
www.redlion.net

MODEL PAXLCL - PAX LITE CURRENT LOOP METER

 DUAL RANGE, 4 to 20 mA or 10 to 50 mA *
 3 1/2-DIGIT, 0.56" (14.2 mm) HIGH RED LED READOUT
 24 VDC EXCITATION SUPPLY
 WIDE SPAN & OFFSET SCALING RANGE
 OVER-RANGE INDICATION
 SELECTABLE DECIMAL POINTS
 NEMA 4X/IP65 SEALED FRONT BEZEL
 OPTIONAL CUSTOM UNITS OVERLAY W/BACKLIGHT

Also adapts to 0 to 50, 0 to 20, 0 to 10, 1 to 5 mA ranges as well as

*

bi-polar inputs.

Bulletin No. PAXLCL-D
Drawing No. LP0567
Released 11/09

U

R

C

L

US LISTED

IND. CONT. EQ.

51EB

GENERAL DESCRIPTION

The premium features of the PAX Lite Series can now be applied to
measurement of process variables. With its high sensitivity and programmability,
the P AX Lite Current Loop Meter can be set up for a wide variety of applications.
In most plants the P AXLCL can be used for 90 to 95% of current loop meter needs
for readout of pressure, flow, temperature, level and other variables. The meter has
been specifically designed for harsh industrial environments. With NEMA 4X/
IP65 sealed bezel and extensive testing of noise effects to CE requirements, the
meter provides a tough yet reliable application solution. This allows the PAXLCL
to be used in dirty, hostile environments and in wash-down areas. The 3 1/2-digit
bi-polar display (minus sign displayed when current or voltage is negative)
features 0.56" (14.2 mm) high, 7-segment LEDs for easy reading.

SAFETY SUMMARY

All safety related regulations, local codes and instructions that appear in the
literature or on equipment must be observed to ensure personal safety and to
prevent damage to either the instrument or equipment connected to it. If
equipment is used in a manner not specified by the manufacturer, the protection
provided by the equipment may be impaired.

CAUTION: Read complete

instructions prior to installation

and operation of the unit.

CAUTION: Risk of electric shock.

DIMENSIONS In inches (mm)

Note: Recommended minimum clearance (behind the panel) for mounting clip installation is

2.1" (53.4) H x 5.0" (127) W.

1

TABLE OF CONTENTS

Ordering Information . . . . . . . . . . . . . . . . . . . .2

General Meter Specifications . . . . . . . . . . . . .3

Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Installing the Meter . . . . . . . . . . . . . . . . . . . . . 4

Setting the Switches . . . . . . . . . . . . . . . . . . . . 4

ORDERING INFORMATION

Meter Part Numbers

PAXL

CL

0

0

Wiring the Meter . . . . . . . . . . . . . . . . . . . . . . . 4

Scaling the Meter . . . . . . . . . . . . . . . . . . . . . .6

Calibrating the Meter . . . . . . . . . . . . . . . . . . . .7

Applications . . . . . . . . . . . . . . . . . . . . . . . . . . .8

CL - Current Loop Meter

Accessories Part Numbers

TYPE PART NUMBERSDESCRIPTIONMODEL NO.

Accessories

PAXLBK30Units Label Kit Accessory PAXLBK

2

GENERAL METER SPECIFICATIONS

1. DISPLAY: 3 1/2-digit, 0.56" (14.2 mm) high, 7-segment red LED, (-) minus

sign displayed when current or voltage is negative. Decimal points inserted
before 1st, 2nd, or 3rd least significant digits by DIP switch selection.

2. OVER-RANGE INDICATION: Indicated by blanking 3 least significant

digits.

3. POWER:

AC Power: 85 to 250 VAC, 50/60 HZ, 6 VA
Isolation: 2300 Vrms for 1 min. between input and supply (300 V working

voltage).

4. INPUT SENSITIVITY: (Numerical Readout Change/mA)

260 units/mA @ 4 to 20 mA input
105 units/mA @ 10 to 50 mA input

(max. allowable input current, 170 mA)

5. COMPLIANCE: Voltage drop across input at max. signal current, less than

600 mV for both 4 to 20 and 10 to 50 mA ranges.

6. INPUT RESISTANCE:

4 to 20 mA - 29.2 
10 to 50 mA - 11.8 

7. SCALING RANGE:
SPAN: 32 coarse steps (binary progression with 5 DIP switches) Each step

providing approx. 8.125 numerical units/mA/step sensitivity for 4 to 20
mA input and 3.25 units/mA/step for 10 to 50 mA input.

OFFSET: 16 coarse steps (binary progression with 4 DIP switches) with ±

switch to add or subtract offset. Each step adds or subtracts approximately
175 from the numerical display for a total offset range of ±2700.

8. LINEARITY: ±(0.05% ±1 digit)

9. READING RATE: 2.5 updated readings/second, nominal.

10. RESPONSE TIME: 1 second to settle for step change.

11. LOW FREQUENCY NOISE REJECTION:

Normal Mode Rejection: 63 dB @ 50/60 Hz
Common Mode Rejection: 100 dB, DC to 50/60 Hz

12. ENVIRONMENTAL CONDITIONS:
Operating Temperature: 0° to 60°C
Storage Temperature: -40° to 80°C
Operating and Storage Humidity: 85% max. relative humidity (non-

condensing)

Span Temperature Coeff.: 100 PPM/°C
Offset Temperature Coeff.: 100 PPM/°C
Vibration According to IEC 68-2-6: Operational 5 to 150 Hz, in X, Y, Z

direction for 1.5 hours, 2 g’s.

Shock According to IEC 68-2-27: Operational 30 g’s, 11 msec in 3 directions.
Altitude: Up to 2000 meters

13. CERTIFICA TIONS AND COMPLIANCES:
SAFETY

UL Recognized Component, File # E179259, UL61010A-1, CSA C22.2 No. 61010-1

Recognized to U.S. and Canadian requirements under the Component
Recognition Program of Underwriters Laboratories, Inc.

UL Listed, File # E137808, UL508, CSA C22.2 No. 14-M95

LISTED by Und. Lab. Inc. to U.S. and Canadian safety standards
Type 4X Enclosure rating (Face only), UL50

IECEE CB Scheme Test Report # 04ME11209-20041018

Issued by Underwriters Laboratories, Inc.

IEC 61010-1, EN 61010-1: Safety requirements for electrical equipment

for measurement, control, and laboratory use, Part 1.
IP65 Enclosure rating (Face only), IEC 529
IP20 Enclosure rating (Rear of unit), IEC 529

ELECTROMAGNETIC COMPATIBILITY

Emissions and Immunity to EN 61326: Electrical Equipment for
Measurement, Control and Laboratory use.

Immunity:

Emissions:

Notes:

1. Criterion A: Normal operation within specified limits.

2. Criterion B: Temporary loss of performance from which the unit self-

recovers.

14. EXCITATION SUPPLY

15. CONNECTIONS: High compression cage-clamp terminal block

Wire Strip Length: 0.3" (7.5 mm)
Wire Gage: 30-14 AWG copper wire
Torque: 4.5 inch-lbs (0.51 N-m) max.

16. CONSTRUCTION: This unit is rated for NEMA 4X/IP65 outdoor use.

IP20 Touch safe. Installation Category II, Pollution Degree 2. One piece
bezel/case. Flame resistant. Panel gasket and mounting clip included.

17. WEIGHT: 0.65 lbs (0.24 kg)

: 24 VDC @ 50 mA max. Regulated and isolated.

Criterion AEN 61000-4-2Electrostatic discharge
4 kV contact discharge
8 kV air discharge
Criterion BEN 61000-4-3Electromagnetic RF fields
10 V/m
Criterion AEN 61000-4-4Fast transients (burst)
2 kV power
2 kV signal
Criterion A EN 61000-4-5Surge
1 kV L-L,
2 kV L&N-E power
1 kV signal
Criterion AEN 61000-4-6RF conducted interference
3 V/rms
Criterion AEN 61000-4-8Power frequency magnetic fields
30 A/m
Criterion AEN 61000-4-11Voltage dip/interruptions

0.5 cycle
Class BEN 55011Emissions

ACCESSORIES

UNITS LABEL KIT (PAXLBK)

Each meter has a units indicator with backlighting that can be customized using

the Units Label Kit (PAXLBK30). The backlight is controlled by a DIP switch.

3

1.0 INSTALLING THE METER

-.00

(92 )

-.0

+.8

3.62

+.03

(45 )

1.77

-.0

+.5

-.00

+.02

LATCHING
TAB S

PAN EL
LATCH

PAN EL
MOUNTING
SCREWS

LATCHING
SLOTS

PAN EL
GASKET

BEZEL

PAN EL

Installation

The PAX meets NEMA 4X/IP65 requirements when properly installed. The
unit is intended to be mounted into an enclosed panel. Prepare the panel cutout
to the dimensions shown. Remove the panel latch from the unit. Slide the panel
gasket over the rear of the unit to the back of the bezel. The unit should be

installed fully assembled. Insert the unit

into the panel cutout.

While holding the unit in place, push the panel latch over the rear of the unit
so that the tabs of the panel latch engage in the slots on the case. The panel latch
should be engaged in the farthest forward slot possible. T o achieve a proper seal,
tighten the latch screws evenly until the unit is snug in the panel (Torque to
approximately 7 in-lbs [79N-cm]). Do not over-tighten the screws.

Installation Environment

The unit should be installed in a location that does not exceed the maximum
operating temperature and provides good air circulation. Placing the unit near
devices that generate excessive heat should be avoided.

The bezel should be cleaned only with a soft cloth and neutral soap product.
Do NOT use solvents. Continuous exposure to direct sunlight may accelerate the
aging process of the bezel.

PANEL CUT-OUT

2.0 SETTING THE SWITCHES

The meter has switches, which must be checked and/or changed prior to
applying power. To access the switches, remove the meter base from the case by
firmly squeezing and pulling back on the side rear finger tabs. This should lower
the latch below the case slot (which is located just in front of the finger tabs). It
is recommended to release the latch on one side, then start the other side latch.

Set-Up DIP Switches

Two banks of DIP switches are located inside the meter. The 10 position bank
of switches are used for calibrating the meter. The values of these switches are
discussed in section 5.0 Calibrating the Meter.

The bank of 4 switches located near the front display are used for the
selection of decimal points and backlight annunciator. Selecting “ON” position
enables the function.

FUNCTIONSWITCH

Decimal Point 1 (000.0)1
Decimal Point 2 (00.00)2
Decimal Point 3 (0.000)3

Backlight Annunciator for Units Label4

3.0 WIRING THE METER

FRONT DISPLAY

Main
Circuit
Board

4
3
2
1

ON

REAR TERMINALS

D.P./ BACKLIGHT

OFFSET

ON

1
2
3

OFFSET

4
5
6
7

SPAN

8
9

10

SPAN

WIRING OVERVIEW

Electrical connections are made via screw-clamp terminals located on the
back of the meter. All conductors should conform to the meter’s voltage and
current ratings. All cabling should conform to appropriate standards of good
installation, local codes and regulations. It is recommended that power supplied
to the meter (AC) be protected by a fuse or circuit breaker.

When wiring the meter, compare the numbers embossed on the back of the
meter case against those shown in wiring drawings for proper wire position. Strip
the wire, leaving approximately 0.3" (7.5 mm) bare lead exposed (stranded wires
should be tinned with solder). Insert the lead under the correct screw-clamp
terminal and tighten until the wire is secure. (Pull wire to verify tightness.)

4

5

4

3

4-20MA

-LOOP

10-50MA

-LOOP

+LOOP

K1

2

1

PAXLCL

4-20MA
XDUCER

EXTERNAL LOOP
POWER SUPPLY

A.C. POWER

(+)

(-)

(+)

4-20mA

POWER SUPPLY

EXTERNAL LOOP

XDUCER

10-50MA

10-50mA

1

2

+LOOP

-LOOP

10-50MA

4-20MA

-LOOP

K1

4

3

5

A.C. POWER

(+)

PAXLCL

(-)

(+)

5

4

3

4-20MA

-LOOP

10-50MA

-LOOP

+LOOP

K1

2

1

PAXLCL

4-20MA
XDUCER

A.C. POWER

(+)

4-20mA

10-50mA

1

2

+LOOP

-LOOP

10-50MA

4-20MA

-LOOP

K1

4

3

5

A.C. POWER

7

(-)

(+)

6

24 VDC

AT 50mA

EXCITATION

SUPPLY

(-)

(-)

7

EXCITATION

SUPPLY

24 VDC

AT 50mA

(+)

6

10-50MA

XDUCER

(-)

(+)

PAXLCL

5

4

3

4-20MA

-LOOP

10-50MA

-LOOP

+LOOP

K1

2

1

PAXLCL

4-20MA

XDUCER

A.C. POWER

(+)

4-20mA

10-50mA

1

2

+LOOP

-LOOP

10-50MA

4-20MA

-LOOP

K1

4

3

5

A.C. POWER

7

(-)

(+)

6

24 VDC

AT 50mA

EXCITATION

SUPPLY

(-)

(-)

7

EXCITATION

SUPPLY

24 VDC

AT 50mA

(+)

6

10-50MA

XDUCER

(-)

(+)

PAXLCL

(+)

EXCITATION

(+)

EXCITATION

EMC INSTALLATION GUIDELINES

1 2

AC

AC

Although this meter is designed with a high degree of immunity to Electro­Magnetic Interference (EMI), proper installation and wiring methods must be
followed to ensure compatibility in each application. The type of the electrical
noise, its source or the method of coupling into the unit may be different for
various installations. Listed below are some EMC guidelines for successful
installation in an industrial environment.

1. The meter should be mounted in a metal enclosure, which is properly

connected to protective earth.

2. Never run Signal or Control cables in the same conduit or raceway with AC

power lines, conductors feeding motors, solenoids, SCR controls, and

heaters, etc. The cables should be run in metal conduit that is properly

grounded. This is especially useful in applications where cable runs are long

and portable two-way radios are used in close proximity or if the installation

is near a commercial radio transmitter.

3. Signal or Control cables within an enclosure should be routed as far away as

possible from contactors, control relays, transformers, and other noisy

components.

4. In extremely high EMI environments, the use of external EMI suppression

devices, such as ferrite suppression cores, is effective. Install them on Signal

and Control cables as close to the unit as possible. Loop the cable through the

core several times or use multiple cores on each cable for additional protection.

3.1 POWER WIRING

AC Power

Terminal 1: VAC
Terminal 2: VAC

Install line filters on the power input cable to the unit to suppress power line
interference. Install them near the power entry point of the enclosure. The
following EMI suppression devices (or equivalent) are recommended:

Ferrite Suppression Cores for signal and control cables:

Fair-Rite # 0443167251 (RLC #FCOR0000)
TDK # ZCAT3035-1330A
Steward #28B2029-0A0

Line Filters for input power cables:

Schaffner # FN610-1/07 (RLC #LFIL0000)
Schaffner # FN670-1.8/07
Corcom #1VR3

Note: Reference manufacturer’s instructions when installing a line filter.

5. Long cable runs are more susceptible to EMI pickup than short cable runs.
Therefore, keep cable runs as short as possible.

6. Switching of inductive loads produces high EMI. Use of snubbers across
inductive loads suppresses EMI.

Snubber: RLC#SNUB0000.

115/230

3.2 INPUT SIGNAL WIRING

2-WIRE, EXTERNAL EXCITATION

NOTES

1. When shielded wire leads are used, connect the shield to earth ground at the meter and insulate the other end to avoid contact with machine ground.

2. Never run signal leads in conduit, bundles, or race ways with power conductors. Avoid runs close to contactors, relays, solenoids, transformers, and other potential
sources of electrical noise.

2-WIRE, WITH EXCITATION (Series Conn.) 2-WIRE, WITH EXCITATION (Parallel Conn.)

5

-500

NUMERICAL READOUT

0

4 8 12 16 20

+500

+1000

+1500

+1999

INPUT SIGNAL CURRENT

Span Adjustment

SPAN 525 (S8 ON)

SPAN 2100 (S6 ON)

SPAN 1050 (S7 ON)

-500

+500

0

+1000

+1500

+1999

INPUT SIGNAL CURRENT

+500 OFFSET

NUMERICAL READOUT

4812 16 20

Offset Adjustment

"ZERO BASE" NO OFFSET

-300 OFFSET

-300

OFFSET

+500

OFFSET

INPUT CURRENT SIGNAL

17.4 Ω

RANGE

10-50MA

11.8 Ω

3

+LOOP

4

(-)

-LOOP

RANGE

4-20MA

(-)

5

-LOOP

K2

5.5K

S6

R

S7

2R

S8

4R

S9

8R

S10

16R

12R

(+)

S5

32R

S1

S4 S3 S2

50R

16R

8R

4R

25R

OFFSET
DIRECTION
SWITCH

(+)
ADD

(-)

SUBTRACT

FINE
OFFSET
ADJUST

25K

R

+V -V

R

CURRENT

SHUNT

RESISTORS

K2

V

II

V

FINE SPAN ADJ.

5K

SPAN=150

SPAN=0

INPUT SIGNAL SCALING CIRCUIT

BUFFER

AMP

SPAN ADJUST

OFFSET ADJUST

A/D

VOLTMETER

CIRCUIT

S3 S2 S1

DIGITAL DISPLAY

DECIMAL

POINT

SWITCHES

DIGITAL VOLTMETER

O

V

1400

700

350

175

2100

1050

525

260

130

mA

S4

SWITCH

ANNUNCIATOR

BACKLIGHT

4.0 SCALING THE METER

PAXLCL SCHEMATIC

DESCRIPTION OF OPERATION

The PAX Lite Current Loop Meter consists of a digital volt meter combined
with an analog scaling circuit (shown above). The unit was designed primarily for
use with 4-20 mA and 10-50 mA current loop signal circuits. However, it can also
be adapted to other current ranges, such as 0-50 mA, 0-20 mA, 0-10 mA, and in
a great many applications it can be used even with 0-5 mA and 1-5 mA current
loops. In addition, input current can be reversed in polarity resulting in negative
numerical readout with a minus (-) sign displayed. Input terminals 3 and 4 are
connected in series with 10-50 mA current loops, and Terminal 3 and 5 are series
connected with 4-20 mA loops. In either case, the voltage drop generated across
the shunt resistor(s) ranges from approximately 0.12 V min. (@ 4 or 10 mA) to

0.59 V max. (@ 20 or 50 mA). The buffer amplifier (K1) conditions and filters
the input signal voltage and applies it to the input of the scaling circuit. The
procedure for scaling P AX Lite Current Loop Meters is simplified by dividing the
scaling process into two separate components, span adjustments and offset
adjustments which are defined in the following discussion.

SPAN ADJUSTMENTS

Span is defined as the numerical range that the display traverses, disregarding
decimal points, when the input signal current is varied from minimum (4 or 10
mA) to maximum (20 or 50 mA). For example, if a unit is to display 25.0 @ 4
mA and 100.0 @ 20 mA, the span is 750 (the difference between 250 and 1000).
Had the minimum display been -25.0 @ 4 mA and +100.0 @ 20 mA, the span
would be 1250 (1000 - (-250) = 1250). (Note: the terms “GAIN”, “SCALE”, and
“SENSITIVITY” are also frequently used interchangeably with the term
“SP AN.”) The PAX Lite Current Loop Meter
can be set up over a very wide span range by
means of the coarse DIP switches S6-S10,
and the fine screwdriver adjustment pot,
located at the back cover. The coarse span
switches add parallel input resistors to the
summing amplifier (K2), thereby increasing
its gain, or sensitivity, as more summing
resistors are added. Effectively, adding more
parallel input resistors, increases the slope of
the transfer curve (at right) and increases the
numerical readout for a given input signal
current change. The input summing resistor values are weighted in a binary
progression, so they can be switched in combinations to give 32 discrete steps of
span. The fine adjust control brackets these coarse steps and can be adjusted to the
exact span needed.

The approximate span contributed by each switch is shown on the rear label.
These values are based on the standard current-loop spans of 4 to 20 mA (16 mA
current variation) and 10-50 mA (40 mA current variation). In other words, if S7
only is turned “ON”, the numerical readout will display a change approximately
1050 for a current swing of 16 mA (4-20 mA input) or 40 mA (10-50 mA input).
If S8 were also turned “ON”, the numerical readout would swing approximately
1575 (1050 for S7 + 525 for S8) for the same signal current variation. The fine
control has a continuous span range of approximately 0-150.

OFFSET ADJUSTMENTS

In the foregoing discussion of span, the transfer curves were shown as
“ZERO-BASED”, i.e., the numerical readout displays “0” when the signal
current goes to zero. With current loop ranges such as 0-5 or 0-10, or 0-20 mA,
and with Bi-Polar (+/-) signals, this is often the desired condition. However,
with 4-20 and 10-50 mA current loops, the minimum current level of 4 or 10
mA usually represents the zero level of the parameter being displayed. There are
also many applications where the
minimum (or zero level) represents some
value that does not fall on a zero based
transfer curve. T o accommodate non-zero
based applications, the PAX Lite Current
Loop Meter has provisions for offsetting
the transfer curve over a wide range.
Essentially, offset moves the transfer
curve up or down to change its intercept
with the numerical readout axis, but it
does not change the slope (SPAN) of the
transfer curve. In the PAX Lite Current
Loop Meter, offset is accomplished by
adding (or subtracting) a constant at the input of the summing amplifier (K2).
This offset constant is summed in with a switched binary resistor network and
a fine adjust offset control in a similar manner to that used for span adjustment.
Switches S2-S5 can be turned on in combinations to give 16 different coarse
offset levels. Each switch is labeled to show the approximate amount of offset
contributed when it is turned “ON”. Switch 1 selects the polarity of the
switched-in offset value and allows offsetting the transfer curve “UP” (adding
the offset constant) or “DOWN” (subtracting). The fine offset control has a
numerical readout range of ±100 and brackets all the coarse switched ranges.

6

5.0 CALIBRATING THE METER

Direct calibration in the signal loop is usually not practical due to the
difficulty in varying the measured parameter and the confusing interaction that
occurs between span and offset adjustments. However, the PAXLCL can be
quickly and easily bench calibrated using a commercially available current
calibrator or the calibration set-up shown below.

CALIBRATION PROCEDURE

The procedure outlined below minimizes span/offset interaction and
simplifies calibration. In Steps 1 to 4 the unit is “nulled” to zero readout with
zero input signal current. In Steps 5 and 6, the span adjustments are made to
establish the required slope of the transfer curve. Then in Step 7, the transfer
curve is shifted up or down as required by setting the offset adjustments. In Step
8, the final “tweaking” adjustments are made at minimum and maximum signal
current. Setting the decimal points in Step 9 completes the calibration.

Before calibrating, the READOUT SPAN (Rs) and SWING CURRENT (Is)
must be determined.

WHERE:

Rs = (Max. Numerical Display) - (Min. Numerical Display) (Disregard Decimal Points)

Is = (Current @ Max. Display) - (Current @ Min. Display)

Example:

Readout is to be 0.00 @ 4 mA and 10.00 @ 20 mA.

READOUT SPAN (Rs) = 1000 - 0 = 1000

SWING CURRENT (Is) = 20 mA - 4 mA = 16

CALIBRATION STEPS

1. Power down the meter and remove it from its case. Turn off all offset and
span adjustment switches (S2-S10 down). S1 has no effect when zeroing
and can be in either position.

2. Turn the span control pot fully counter-clockwise (20 turns max.).

3. Turn on a combination of span adjust switches (6-10) to obtain a total value
closest to (but not greater than) the READOUT SPAN (Rs) desired (1000
in this example). The following chart gives an approximate span
adjustment value for each switch:

SWITCH NUMBER SPAN VALUE

6 2100
7 1050

8 525
9 260

10 130

4. Place unit in its case and apply power. Apply zero current. Adjust the
indicator to read zero using the offset adjustment pot.

5. Apply the SWING CURRENT (Is) (16 mA in the example) to the input.
Set the exact READOUT SPAN value (1000) with span adj.pot.

6. Apply zero current to see if the zero value has shifted. If it has, re-zero with
the offset pot, then repeat Step 5.

7. After the span has been adjusted, set the signal current to the minimum
level (4 mA in the example). Record the meter reading (in this example the
reading will be 250). Subtract the desired reading at minimum current
value (0 in the example) from the recorded reading (0-250 = - 250). Power
down the meter and remove it from its case. Set the offset add/subtract
switch S1 (subtract = on), and the offset switches (S2-S5) to obtain a total
value closest to (but no more than) the difference between the desired
reading at minimum current value and the observed reading The following
chart gives an approximate offset adjustment value for each switch:

OFFSET VALUESWITCH NUMBER

14002

7003
3504
1755

Place the meter in its case and apply power. Using the offset adjust pot,
adjust the readout to equal the desired reading at the minimum current
value (0 in the example).

8. Adjust the input signal current to its maximum value to see if the proper
readout is obtained (1000 @ 20 mA in the example). If the readout is
slightly off, adjust the span pot to obtain the true reading. Then, recheck
the reading at the minimum input current (4 mA) and readjust the offset
pot if necessary. Repeat the maximum and minimum readout adjustments
until the unit displays the proper readout at both extremes.

9. Set decimal points as desired using the three decimal point switches. The
unit can now be installed.

TROUBLESHOOTING

For further assistance, contact technical support at the appropriate company

numbers listed.

The Company warrants the products it manufactures against defects in materials and workmanship

LIMITED WARRANTY

for a period limited to two years from the date of shipment, provided the products have been stored,
handled, installed, and used under proper conditions. The Company’s liability under this limited
warranty shall extend only to the repair or replacement of a defective product, at The Company’s
option. The Company disclaims all liability for any affirmation, promise or representation with
respect to the products.

The customer agrees to hold Red Lion Controls harmless from, defend, and indemnify RLC
against damages, claims, and expenses arising out of subsequent sales of RLC products or products
containing components manufactured by RLC and based upon personal injuries, deaths, property
damage, lost profits, and other matters which Buyer, its employees, or sub-contractors are or may be
to any extent liable, including without limitation penalties imposed by the Consumer Product Safety
Act (P.L. 92-573) and liability imposed upon any person pursuant to the Magnuson-Moss Warranty
Act (P.L. 93-637), as now in effect or as amended hereafter.

No warranties expressed or implied are created with respect to The Company’s products except
those expressly contained herein. The Customer acknowledges the disclaimers and limitations
contained herein and relies on no other warranties or affirmations.

7

1375

OFFSET

READOUT

NULL

40

B SPAN

10

50

MA

MA

MA

CURRENT

D

CHECK

C

A

6.0 APPLICATIONS

C

A

D

CHECK

READOUT

B

CURRENT

(+)(-)

-15MA-9MA-6
MA

-900

+900

OFFSET

NULL

SPAN

SPAN

OFFSET

CURRENT

(-)

4

MA

B

8

MA

20

MA

-1500

NULL

A

(+)

C

READOUT

+1500

D

CHECK

CHECK

D

Example 1:

A PAXLCL is to be calibrated to match a flow transducer whose output is 10

mA @ 0 GPM and 50 mA @ 1375 GPM.

READOUT SPAN (Rs) = 1375  0 = 1375
SWING CURRENT (Is) = 50 mA  10 mA = 40 mA

ADJUSTMENTS (Refer to the transfer curve below)

Null the unit to zero readout @ 0



current per Steps 1 to 4 of the
calibration steps.

Set the coarse and fine span adjustments



to get a readout of 1375 @ 40 mA per
Steps 5 and 6. Note: With the full

standard swing of 40 mA, the coarse
span switch reference markings can be
used to determine settings as follows:

S7 ON (1050) + S9 ON (260) = 1310

Span set with switches.

375 (needed) - 1310 (with SW’s) = 65

w. fine span adj.

Set offset to readout 0 @ 10 mA per Step 7. Note: The read out observed



when the 10 mA min. current is first applied can be used to determine the
offset switch settings.) In this example the readout will be (+) 344 when the

10 mA min. current is first applied. Applying -344 offset then reduces the
readout to zero @ 10 mA.

Check readout at max. (50 mA) and min. (10 mA) and fine tune (tweak) as



required per Step 8.

Example 2 (Negative Slope):

A level measuring device puts out 6 mA when a storage tank is full and 15
mA when the tank is empty. The PAXLCL is to readout 90.0 tons at full tank
and zero when empty.

READOUT SPAN (Rs) = 900  0 = 900 (Disregard Decimal Points)

SWING CURRENT (Is) = 6 mA (@ max rdg) - 15 mA (@ min rdg) = -9 mA

In this case, the signal current is reverse [Term 3 (-) with respect to Term 5

(+)] causing the readout to go “down” (increasingly negative) as the negative

current increases.

ADJUSTMENTS

Null the unit per Steps 1 to 4.



Set slope of transfer curve with span



adjustments to get readout of -900
@ -9 mA per Steps 5 and 6.

Move transfer curve up by applying



(+) offset per Step 7 until readout is
+900 @ -6 mA.

Check extreme readings per Step 8,



0 readout @ -15 mA and +900
readout @ -6 mA. Set D.P. Switch
S1 and replace unit in case.

Example 3 (± Display):

A differential pressure transducer has a range of ±1500 PSI with a 4 to 20 mA

output (-1500 @ 4 mA, +1500 @ 20 mA).

READOUT SPAN (Rs) = +1500 (1500) = 3000
SWING CURRENT (Is) = 20 mA(max) - 4 mA(min) = 16 mA

Note: Since the display readout is limited to 1999 numerical indication, the

full READOUT SPAN of 3000 cannot be obtained during zero based span
adjustment. However, dividing both the READOUT SPAN and SWING
CURRENT by two, i.e. 1500 readout @ 8 mA, allows the span adjustment
to be made for the proper transfer curve slope.

ADJUSTMENTS

Null the unit per Steps 1 to 4.



Set transfer curve slope with span



adjustments per Steps 5 and 6, to get
a readout of +1500 @ 8 mA.

Apply (-) offset per Step 7 to get a



reading of -1500 @ 4 mA.

Check min. and max. extremes and



tweak if required to get desired
readout @ 4 and 20 mA per Step 8.

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