Vega DSGH Quick Reference Manual

Quick Reference Guide

DSGH

®

Radiation-Based Detector with GEN2000

®

Electronics for Density Measurement

Document ID:
31524

Nuclear

Revision History

Revision History

Version of manual

Description

Date

1.0

Initial release

051025

1.1

Electronics revision

090306

1.2

Added perforated view for ground - Wiring

090811

1.3

Changed company name, logo, and website

110301

1.4

Removed one point calibration

111121

1.5

Changed page layout to A5

130403

This document contains proprietary information of VEGA Americas, Inc. It shall not be
reproduced in whole, or in part, in any form, without the expressed written permission of
the VEGA Americas, Inc.

The material in this document is provided for informational purposes only and is subject
to change without notice.

ISO 9001 approval by Lloyd's Register Quality Assurance Limited, to these Quality
Management System Standards: ISO 9001:2000, ANSI/ASQC Q9001-2000, Approval
Certificate No. 107563.

3

Notes

NOTES

4

Table of Contents

Table of Contents

Revision History ................................................................................ 3

Table of Contents .............................................................................. 5

Wiring ................................................................................................. 7

Current Loop Output ...................................................................................... 9

Auxiliary Input Frequency Signal ................................................................... 9

Relay ............................................................................................................. 9

RS-485 ........................................................................................................ 10

Setup and Calibration ..................................................................... 11

Current Loop (analog output calibration) ..................................................... 11

Set up 4 mA ........................................................................................................ 11

Set up 20 mA ...................................................................................................... 11

Select Linearity ................................................................................................... 12

Calibrate Gauge .................................................................................................. 12

Maintenance and Diagnostics ........................................................ 15

Alarm Types ................................................................................................ 15

Gauge Status ............................................................................................... 16

Diagnostic Screens in Ohmview 2000 .............................................................. 16

Acknowledge Diagnostic Alarms ......................................................................... 16

Diagnostic Alarm Messages and Conditions ....................................................... 16

Troubleshooting ........................................................................................... 19

Test points .......................................................................................................... 19

LED Indicators .................................................................................................... 20

Field Repair Procedures .............................................................................. 22

Replace CPU or Power Supply Board ................................................................. 23

Periodic Maintenance .................................................................................. 23

Customer Service ............................................................................ 24

5

Notes

NOTES

6

Wiring

Wiring

Follow the diagram and the steps below for wiring connections.

1. Make connections at the removable terminal strips mounted on the power board.

2. Access the power board by removing the explosion-proof housing cap.

3. Connect the power earth ground wire with the internal and external ground screw.

4. Access the ground screws by removing the top cover.

Interconnecting Terminals – GEN2000 HART

1 Power In (L)
2 Power In (N)
3 Relay Normally Open (NO)
4 Relay Common (C)
5 Relay Normally Closed (NC)
6 Frequency +
7 Frequency ­8 + 6V Auxiliary Input Power (Not used in HART Applications)
9 Common
10 -6V Auxiliary Input Power
11 Auxiliary Input Frequency Signal +
12 Auxiliary Input Frequency Signal ­13 Current Loop Output +
14 Current Loop Output –

7

Wiring

DSGH Exploded View

1 Power Supply Board
2 CPU Board

DSGH Perforated View

1 Customer Earth Ground and Ground to Housing

Do not apply power until thoroughly checking all the wiring. Not all
connections are required for operation. For example, Terminal 10
(

-6V, Auxiliary Input Power) may not be used with newer electronics. The

power input terminals are not polarity

-sensitive.

8

Wiring

• The AC power source voltage input is 100 - 230 VAC ±10% (90 - 250 VAC) at 50/60

Hz, at 15 VA (or 25 VA with optional heater) maximum power consumption.

• Do not share the AC power with transient-producing loads. Use an individual AC

lighting circuit. Supply a separate earth ground.

• The DC power source voltage input is 20–60 VDC (<100 mV, 1/1,000 Hz ripple) at

15 VA maximum power consumption. DC power cable can be part of a single cable
4-wire hookup, or can be separate from output signal cable.

• Wire must meet power per local code.

• Use wire suitable for +40 °C (104 °F) above surrounding ambient temperature.

• All field wiring must have insulation suitable for 250 volts or higher.

Not all connections are required for operation. The power input terminals are

not polarity-sensitive. The HART signal may not operate with some isolating
barriers or other non-resistive loads.

Current Loop Output

The current loop output signal is 4 … 20 mA into 250 - 800 Ω load. Pin 13 is positive (+)
and Pin 14 is negative (-). HART communication protocol (BEL202 FSK standard) is
available on these connections. The output is isolated to standard ISA 50.1 Type 4
Class U.

When using signal (4 … 20 mA output) cables (customer supplied), they must meet
these specifications:

• Maximum cable length is 3,280 ft. (1,000 m)

• All wires should be per local code

When using DC power, the signal and power can run on a single cable 4-wire hookup (2
wires for power, 2 wires for 4... 20 mA).

Auxiliary Input Frequency Signal

Frequency input signal is 0/100 kHz ≤, true digital.

Relay

Relay contacts are rated at 6 A at 240 VAC, 6 A at 24 VDC, or 1/4 HP at 120 VAC.
Frequency input signal is 0/100 kHz ≤, true digital.

9

Wiring

RS-485

The CPU board contains clearly labeled RS-485 connections. Use shielded wire per
local code at a maximum length of 2,000 ft. (609 m).

1. Connect positive terminals together.

2. Connect negative terminals together.

3. Connect ground terminals together.

10

Setup and Calibration

Setup and Calibration

Before using the gauge to make measurements, you must:

• Calibrate it to relate the detection of radiation from the source to the level of the

process material.

• Calibrate the current loop to a reference ammeter or the DCS.

Current Loop (analog output calibration)

Before completing a current loop calibration:

1. Connect an ammeter anywhere along the current loop (in series).

2. Make sure there is a 250 - 800 Ω load on the current loop. If no load or an

insufficient load exists on the loop, it may require temporary placement of a resistor.

3. Hook the meter in series with the load resistor.

4. Open Ohmview 2000

Perform the following steps to calibrate the current loop.

Set up 4 mA

1. Click Calibration, Current Loop Cal.

2. Click Execute.

3. Click OK.

4. Read the ammeter and enter the actual milliamp reading.

5. Click OK.

6. Click YES if the ammeter reads 4.00 mA or NO for any other reading.

7. Repeat until the meter reads 4.00 mA.

8. Read the ammeter and enter the actual milliamp reading.

9. Click OK.

10. Click OK.

Set up 20 mA

1. Read the ammeter and enter the actual milliamp reading.

2. Click OK.

3. Click YES if the ammeter reads 20.00 mA or NO for any other reading.

4. Repeat until the meter reads 20.00 mA.

5. Read the ammeter; enter the actual milliamp reading.

6. Click OK.

7. Click OK.

11

Setup and Calibration

Select Linearity

The majority of density applications use the equation linearizer to calculate the process
value. For density applications, the equation is the default and we recommend it in most
circumstances. If the results from the equation linearizer method are not satisfactory,
contact VEGA Field service to explain the other options. The linearizer equation
calculates a density reading for a given count reading at the detector. To make the
correct calculation, it relies on the following information:

• Vessel’s inner diameter system parameter

• Span settings parameter

• Source type parameter

• Data used in the initial calibration

• Absorption co-efficient

For information on linearity options, see the DSGH Installation and Operation Guide.

1. Click Setup, Gauge Setup, Linearizer Type.

2. Click Equation.

Calibrate Gauge

To calibrate your gauge, you must complete the Standard Method (2-point) or the
Two-Point Process Calibration steps.

Standard Method (2-point)

1. Set the low density and collect Cal Low data.

2. Set the high density and collect Cal High data.

3. Collect the linearizer table data.

4. Calculate the linearity.

5. Calculate the calibration.

6. Perform the data collection steps in any sequence, depending on your ability to

empty and fill the vessel.

To perform a calibration you must complete the following:

1. Click Equation from the Setup, Gauge Setup tab.

2. Check that the parameters (vessel inner diameter, engineering units, measurement

span, and source type) are correct.

3. Start the gauge 4 hours before start of calibration.

4. Fill vessel or pipe with process.

5. Prepare to draw a sample while the gauge is collecting data.

6. Measure a process sample with the density gauge and enter the actual density.

12

Setup and Calibration

The accuracy of the calibration depends upon the accuracy of the sample.
Obtain an accurate reading, from a laboratory, of the sample read by the
gauge.

Two Point Process Calibration (Preferred Method)

You must provide the high and low process conditions when performing a two-point
calibration. If using the standard method, record both the sensor counts and levels at
each step:

Set Low Density

1. Click Calibration, 2 Point Calibration, Cal Low Collect.

2. Click Start.

3. Click Accept.

4. Enter the actual process value (from the laboratory) in engineering units.

5. Click OK.

Set High Density

1. Click Calibration, 2 Point Calibration, Cal High Collect.

2. Click Start.

3. Click Accept.

4. Enter the actual process value (from the laboratory) in engineering units.

5. Click OK.

Collect Linearizer Table Data

1. Click Calibration, Linearizer Data Pt, Create Data Point.

2. At the prompt, enter the known process value.

3. Accept or reject the results when they appear.

4. Repeat the procedure for all available values

Calculate Calibration

1. Click Calibration, 2 Point Calibration.

2. Click Calculate Results.

3. Click OK.

4. Click OK.

13

Notes

NOTES

14

Maintenance and Diagnostics

Maintenance and Diagnostics

The transmitter system alerts you to detector problems by:

• Posting messages on the Ohmview 2000 message screen.

• De-energizing the output relay.

• Distinctly changing the current loop output.

• Tracking the current status and history in the Gauge status screens.

Alarm Types

Name

Description

Diagnostic

Diagnostic alarm provides information about level gauge system and alerts users

when periodic procedures are due.

Analog

Analog alarm sets the current loop mA to 2 mA or 22 mA when detector outputs zero

(0) counts.

If analog alarm is on, check the following:

• Is source holder shutter in On or Open position to create the required radiation

field?

• Is there extreme build-up on walls or other material that is shielding detector

from radiation field?

• Are electrical connections from sensor assembly to CPU board damaged or

disconnected?

Process

Process alarm triggers when process level is above or below a set point (high limit or

low limit).

Enter choice of low or high limit and set point on Alarm | Relay Setup tab. This
alarm only works for output relay.

The gauge acknowledges or resets process alarm when process value returns to set
point value.

X-ray

X-ray alarm changes current loop mA output in response to marked increase in

radiation field. This change prevents control problems when external radiographic
sources are in the area during vessel inspections. Gauge sets current loop output at
value measured 10 seconds before condition. Gauge cycles until radiation field is
back to normal level or until a time-out period of 60 minutes passes.

15

Maintenance and Diagnostics

Excessive radiation fields at the detector can permanently damage the
gauge. The device has a protection feature that safeguards against
excessive radiation fields. The procedure for activating this protection is
firmware dependent. Please consult the factory to activate this feature on
your device.

Alarm Output

Diagnostic

Analog

Process

X-ray

Option to trigger relay

√

√ √

Display HART message Optional

Current loop output affected

√ √ Gauge status and gauge history

√

Gauge Status

Diagnostic Screens in Ohmview 2000

• To check the system’s present status, click Diagnostics, Diagnostics tab.

• For historical information, click the Diagnostic History and STDZ History tabs.

Since some conditions are self-repairing such as RAM and EEPROM corruption, these
conditions may appear in history screens, but not in diagnostic screens.

Acknowledge Diagnostic Alarms

Diagnostic alarms turn off when the problem resolves except for the following reasons:

• Source wipe due

• Shutter check due

• Standardize due

If the relay is set as a diagnostic alarm, you must acknowledge all diagnostic

alarms to reset the relay.

Diagnostic Alarm Messages and Conditions

View active alarm messages on the Ohmview 2000 menu. Use the Alarms, Diagnostic
Alarm Enable tab to select alarm messages.

16

Maintenance and Diagnostics

When a HART device initially connects to the gauge, any conditions in alarm appear.

Condition

Description

Action

RAM Status ­Pass/Fail

RAM corrupt/RAM memory corruption
occurred and resolved internally.
Repeated triggering of alarm suggests
hardware problem.

Consult VEGA Field Service.

Sensor EEPROM -

Pass/Fail

Sensor EEPROM corrupt/ Critical

memory corruption occurred on
sensor pre-amp board EEPROM may
not be resolved internally. If alarm
recurs, suggests hardware problem.

Check for recurrence by

acknowledging alarm. Cycle power
to unit.

If it recurs, contact VEGA Field
Service.

Real Time Clock

Status - Pass/Fail

Real time clock failed/Can cause

miscalculation of timed events.

Reset time and date. Contact VEGA

Field Service if clock does not reset.

Note: If gauge has been without
power for 28 days or greater, you
must reset clock.

Sensor Temp

Probe - Pass/Fail

Sensor temp probe fail/Sensor

temperature probe may not be
functioning, which results in
erroneous measurements.

Verify sensor temperature on

Diagnostics, Process Chain tab. If
temperature reads - 0.5 °C (+31 °F)
constantly, probe may be broken and
CPU board may need replacement.
Contact VEGA Field Service.

Source Wipe Due ­No/Yes

Source wipe due Perform source wipe. Log shutter

check on Source Functions tab.

CPU EEPROM -

Pass/Fail

CPU EPPROM corrupt/Critical

memory corruption occurred on CPU
board EEPROM may not be resolved
internally.

If alarm recurs, suggests hardware
problem.

To check for recurrence,

acknowledge alarm. Cycle power to
unit.

If it recurs, contact VEGA Field
Service for advice.

Sensor Status -

Pass/Fail

Sensor fail/ Less than 1 count seen in
last 10 seconds (configurable by Field

Service.) Indicates sensor is
malfunctioning.

Contact VEGA Field Service.

17

Maintenance and Diagnostics

Sensor Voltage

Status - Pass/Fail

Sensor high voltage fail/High voltage

on PMT is outside usable range.

Contact VEGA Field Service.

Standardize Due -

No/Yes

Standardize Due

Perform a new standardization

procedure.

Shutter Check Due

- No/Yes

Shutter Check Due

Perform shutter check. Acknowledge

on Source Functions tab.

New Hardware

Found - No/Yes

New hardware found?/CPU board

detects configuration mismatch. CPU
board or sensor assembly may have
been replaced or one of EEPROM
configurations is incorrect.

Contact VEGA Field Service first. If

they concur, click Diagnostics, New
Hardware, No New Hardware and
click OK.

Process Out of

Range - No/Yes

Process out of measurement

range/Current process value is not
within limits set by Max level and Min
level in gauge span settings.

Contact VEGA Field Service.
X-Ray Alarm -

No/Yes

Note that there are high levels of x-ray

radiation in area that can affect
process measurement.

Contact VEGA for more information.

18

Maintenance and Diagnostics

Troubleshooting

Two circuit boards are field-replaceable.

Power Supply Board and CPU Board

Test points

Power Supply Board

Label

Description

H1 HART connection

H2

HART connection

TP1

Isolated ground

TP2

Loop current test point 200 mV/mA loop current, referenced to isolated ground

19

Maintenance and Diagnostics

CPU board

Label

Description

Count Raw input signal coming from the preamplifier

GND

Logic ground

U5 pin 8

+5V power supply test point, referenced to logic ground

Jumpers

Jumpers JP1 and JP2 on the power supply board set the current loop source or sink
mode. The gauge does not use jumpers J1 through J4 on the CPU board.

Do not change the jumpers from the current setting without calling VEGA
Field Service.

Mode

Gauge Current Loop

Jumper Setting

Source mode

Self-powered

JP1 Pins 1-2, JP2 Pins 2-3

Sink mode

DCS-powered

JP1 Pins 2-3, JP2 Pins 1-2

LED Indicators

Power Supply Board

LED

Description

Normal

Condition

Error Condition

Recommendation

+6V

+6V DC

voltage level to
electronics

ON

OFF - electronics

are not receiving
+6 V DC required
for functioning

Verify +6 V on pin 8 of terminal strip

(Pin 9 can be used as ground
reference. Check fuse on power
supply board. Check power input
terminals 1 and 2.

+24V

Analog output

loop voltage

ON

OFF - 24 V not

present on 4 ... 20
mA output and
HART

communications

Check loop wiring and jumpers JP1,

JP2 on power supply board.
Replace power supply board.

20

Maintenance and Diagnostics

are bad

Relay Relay

condition
indicator

ON - relay
energized.

OFF - relay
de-energized

None Check against relay output

terminals 3, 4, and 5. If no relay
output, replace power supply
board.

CPU Board

Use the LED indicators on the CPU board to check the basic functioning of the gauge.
They are visible when you remove the explosion-proof housing pipe cap.

LED Indicators – CPU Board

If the LED band displays the Memory Corrupt pattern, call VEGA Field
Service to report this condition. The gauge does not operate if the FLASH
chip is corrupt.

CPU

LEDs

Description Normal Condition Error Condition Recommendation

Mem

Memory

corruption

OFF

Blink Pattern

1-CPU EEPROM
corrupt

2-Sensor EEPROM
corrupt

3-Both EEPROMs
corrupt

4-RAM corrupt

5-Memory mismatch

ON solid­Combination of
errors

Check software

diagnostics. Call
VEGA Field
service.

HART

HART
communication

ON - blinks when
receiving HART

None

Check device and

21

Maintenance and Diagnostics

indicator

messages

connection on loop

CPU Central

processing unit

Blinks at rate of once
per second

LED does not blink.
CPU not functioning

Check power
input. Replace
CPU board.

Aux

Auxiliary input

frequency signal
indicator

Blinks if auxiliary input is

present

None

Check auxiliary

input wiring
terminals 11 and
12 with meter for
frequency signal.
Check auxiliary
input equipment.

HV

Sensor high

voltage

On - high voltage is

within specification

Off-high voltage is

outside of
specification

Call VEGA Field

Service.

Field

Radiation field

indicator

Cycles in proportion to

radiation field intensity
at detector. On for 10
seconds for each
mR/hr, then off for 2
seconds. (Use LED 5,
which blinks 1
time/second to time
LED1 for field indicator.)

None

Check for closed

source shutter,
buildup, and/or
insulation.

Field Repair Procedures

Use appropriate electrostatic discharge procedures to prevent damage to
the electrical components of the gauge.

Before replacing a circuit board, call VEGA Field Service.

The sensor EEPROM contains a backup of the CPU board EEPROM. After replacing
the CPU board, you must perform a memory backup to update the CPU board’s
EEPROM with the information in the sensor board EEPROM.

22

Maintenance and Diagnostics

Replace CPU or Power Supply Board

1. Turn off power to the gauge.

2. Remove the housing cover.

3. Remove the plastic electronics cover.

4. Remove the terminal wiring connector.

5. Remove the three (3) screws holding the electronics package in place.

6. Carefully pull the electronics package out of the housing.

7. Remove the appropriate board from the clamshell assembly by removing the three

(3) mounting nuts.

If you are changing the CPU board, you must move the old firmware chip to
the new board if the new board firmware is different.

8. Carefully reconnect any ribbon cables.

9. Install the electronics package in the housing.

10. Replace the three (3) mounting nuts.

11. Reconnect the terminal wiring connector.

12. Install the plastic electronics cover.

13. Install the housing cover.

14. Turn on the power to the unit.

15. Connect a HART communicator to the unit and verify that the unit is operational.

If you change the CPU board, a New Hardware Found error message
normally appears when you connect with the HART communicator. In

Ohmview 2000, click Diagnostics, New hardware, New CPU and click OK for

a new backup of EEPROMS.

Periodic Maintenance

Follow this suggested schedule to prevent problems and to comply with radiation
regulations.

• Recalibrate - As required by process conditions.

• Source holder shutter check - Every 6 months unless otherwise required by the

appropriate nuclear regulatory body.

• Source wipe - Every 3 years unless otherwise required by the appropriate nuclear

regulatory body.

23

Notes

NOTES

24

Customer Service

Customer Service

VEGA has Field Service Engineers or Radiation Safety Officers available for onsite
service, emergency services, or equipment start up.

Contact Information

Telephone Number

Monday through Friday 8:00 A.M. - 5:00 P.M. EST

(Eastern Standard Time)

1-513-272-0131

Emergencies: Follow the voice mail instructions 1-513-272-0131

Fax

1-513-272-0133

25

Notes

NOTES

26

VEGA Americas, Inc.
4170 Rosslyn Drive
Cincinnati, Ohio 45209 USA
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]

www.vega-americas.com

31524-US-130403

Subject to change without prior notice

2013© VEGA Americas, Inc. Cincinnati, Ohio, USA

All statements concerning scope of delivery, application,

practical use, and operating conditions of the sensors

and processing systems correspond to the information

available at the time of printing.