MSA TRIGARD® Gas Monitoring System Owner's manual

TRIGARD

®

Gas Monitor

Instruction Manual

THIS MANUAL MUST BE CAREFULLY READ BY ALL INDIVIDUALS WHO HAVE OR WILL

HAVE THE RESPONSIBILITY FOR USING OR SERVICING THE PRODUCT. Like any piece

of complex equipment, this instrument will perform as designed only if it is used and

serviced in accordance with the manufacturer’s instructions. OTHERWISE, IT COULD

FAIL TO PERFORM AS DESIGNED AND PERSONS WHO RELY ON THIS PRODUCT FOR

THEIR SAFETY COULD SUSTAIN SEVERE PERSONAL INJURY OR LOSS OF LIFE.

The warranties made by Mine Safety Appliances Company with respect to the product are

voided if the product is not used and serviced in accordance with the instructions in this

manual. Please protect yourself and others by following them. We encourage our cus-

tomers to write or call regarding this equipment prior to use or for any additional infor-

mation relative to use or repairs.

In North America, to contact your nearest stocking location, dial toll-free 1-800-MSA-INST

To contact MSA International, dial (724) 776-8626

This manual is available on the internet at www.msasafety.com

Manufactured by

MSA NORTH AMERICA

1000 Cranberry Woods Drive, Cranberry Township, Pennsylvania 16066

(L) Rev 3 10072857

"! WARNING

MSA Instrument Warranty

1. Warranty- Seller warrants that this product will be free from

mechanical defect or faulty workmanship for a period of eighteen

(18) months from date of shipment or one (1) year from installation,

whichever occurs first, provided it is maintained and used in

accordance with Seller’s instructions and/or recommendations.

This warranty does not apply to expendable or consumable parts

whose normal life expectancy is less than one (1) year such as,

but not limited to, non-rechargeable batteries, sensor elements,

filter, lamps, fuses etc. The Seller shall be released from all

obligations under this warranty in the event repairs or modifications

are made by persons other than its own or authorized service

personnel or if the warranty claim results from physical abuse or

misuse of the product. No agent, employee or representative of the

Seller has any authority to bind the Seller to any affirmation,

representation or warranty concerning the goods sold under this

contract. Seller makes no warranty concerning components or

accessories not manufactured by the Seller, but will pass on to the

Purchaser all warranties of manufacturers of such components.

THIS WARRANTY IS IN LIEU OF ALL OTHER

WARRANTIES, EXPRESSED, IMPLIED OR STATUTORY, AND IS

STRICTLY LIMITED TO THE TERMS HEREOF. SELLER

SPECIFICALLY DISCLAIMS ANY WARRANTY OF

MERCHANTABILITY OR OF FITNESS FOR A PARTICULAR

PURPOSE.

2. Exclusive Remedy- It is expressly agreed that Purchaser’s sole

and exclusive remedy for breach of the above warranty, for any

tortious conduct of Seller, or for any other cause of action, shall be

the repair and/or replacement at Seller’s option, of any equipment

or parts thereof, which after examination by Seller is proven to be

defective. Replacement equipment and/or parts will be provided at

no cost to Purchaser, F.O.B. Seller’s Plant. Failure of Seller to

successfully repair any nonconforming product shall not cause the

remedy established hereby to fail of its essential purpose.

3. Exclusion of Consequential Damage- Purchaser specifically

understands and agrees that under no circumstances will seller be

liable to purchaser for economic, special, incidental or

consequential damages or losses of any kind whatsoever, including

but not limited to, loss of anticipated profits and any other loss

caused by reason of nonoperation of the goods. This exclusion is

applicable to claims for breach of warranty, tortious conduct or any

other cause of action against seller.

General Warnings and Cautions

1. The Trigard Gas Monitors described in this manual must be

installed, operated and maintained in strict accordance with their

labels, cautions, warnings, instructions, and within the limitations

stated.

2. The Trigard Gas Monitor is designed to detect gases or vapors in

air. It cannot measure the concentration of gases or vapors in

steam or inert or oxygen-deficient atmospheres. The oxygen

sensor can measure oxygen-deficient atmospheres.

3. Electrochemical sensors are sealed units which contain a corrosive

electrolyte. Should a sensor develop leakage, it must be

immediately removed from service; then, remove it from the

sensing head and discard it properly. Caution must be exercised so

that the electrolyte does not contact skin, eyes, clothing or circuitry;

otherwise, serious personal injury (burns) and/or equipment

damage may result.

4. Use only genuine MSA replacement parts when performing any

maintenance procedures provided in this manual. Failure to do so

may seriously impair instrument performance. Repair or alteration

of the Trigard Gas Monitor, beyond the scope of these

maintenance instructions or by anyone other than an authorized

MSA service personnel, could cause the product to fail to perform

as designed and persons who rely on this product for their safety

could sustain serious personal injury or death.

5. Do not locate the general-purpose enclosure models in an area

which may contain a flammable mixture of gas and air; otherwise,

an explosion may occur. The general-purpose Trigard Gas

Monitors can be a source of ignition and must not be mounted in

an area where a flammable mixture of combustible gas and air

may become present; otherwise, an explosion may occur.

Failure to follow the above can result in serious personal

injury or death.

"

WARNING

i

1. As with all gas monitors of these types, high levels of, or long

exposure to, certain compounds in the tested atmosphere could

contaminate the sensors. In atmospheres where Trigard Gas

Monitor may be exposed to such materials, calibration must be

performed frequently to ensure that operation is dependable and

display indications are accurate.

2. The Trigard Gas Monitor must not be painted. If painting is done in

an area where a Monitor is located, care must be exercised to

ensure that paint is not deposited on the sintered, metal flashback

arrestor in the inlet fitting of the Trigard Gas Monitor, if so

equipped. Such paint deposits would interfere with the diffusion

process, whereby a sample of the atmosphere being monitored

diffuses into the Monitor.

3. The only absolute method to ensure proper overall operation of

Trigard Monitor is to check it with a known concentration of the gas

for which it has been calibrated. Consequently, calibration checks

must be included as part of the routine inspection of the system.

4. Protect the Trigard Gas Monitor from extreme vibration. Do not

mount the sensing head in direct sunlight as this may cause

overheating of the sensor.

Failure to follow the above can result in injury, product

damage and/or an unsafe condition.

"

CAUTION

ii

Table of Contents

Chapter 1,

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1

General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1

Identifying Your Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1

Installing Your Gas Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2

Installing the Trigard Gas Monitor . . . . . . . . . . . . . . . .1-3

Electrical Connections for Trigard Gas Monitors . . . . . . . . . . .1-3

Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3

For Milliamp Output . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4

Typical Trigard Gas Monitor Wiring . . . . . . . . . . . . . . . . . . . . .1-5

Installing the Trigard Remote Sensor Module . . . . . . . . . . . . .1-7

Electrical Connections for the Trigard

Remote Sensor Module . . . . . . . . . . . . . . . . . . . .1-9

At the Trigard Remote Sensor Location: . . . . . . . . . .1-10

Chapter 2,

Start-up and Calibration for 4-20 mA Output . .2-1

Initial Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1

Calibration Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

Chemicals that Reduce Catalytic Sensor Sensitivity . .2-4

Ultima Calibrator . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

Ultima Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

Note on Resetting Latched Alarms

with Controller or Calibrator . . . . . . . . . . . . . . . . . . . . .2-6

Trigard Gas Monitor Calibration Output Signal . . . . . .2-6

Calibration Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6

Trigard Gas Monitor Calibration Procedure . . . . . . . . . . . . . . .2-7

INITIAL Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7

Regular Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8

Zeroing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8

Spanning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10

Calibration Documentation . . . . . . . . . . . . . . . . . . . .2-12

iii

Chapter 3,

Start-up and Calibration for MODBUS output . .3-1

Typical ModBUS Network Topography (FIGURE 3-1). . . . . . .3-1

Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1

Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1

Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1

RS485 Communications . . . . . . . . . . . . . . . . . . . . . . .3-1

Transmitter Sensor Distance . . . . . . . . . . . . . . . . . . .3-1

Typical Communication Cable Wiring . . . . . . . . . . . . . . . . . .3-5

Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5

Alarm Status Screen . . . . . . . . . . . . . . . . . . . . . . . . . .3-7

Ultima Controller or Ultima Calibrator: . . . . . . . . . . . . .3-8

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-9

ModBUS Communications . . . . . . . . . . . . . . . . . . . . .3-10

ModBUS Addressing . . . . . . . . . . . . . . . . . . . . . . . . .3-10

ModBUS Communications . . . . . . . . . . . . . . . . . . . . .3-11

ModBUS Base Address (Read/Write) . . . . . . . . . . . .3-12

Chapter 4,

Additional Features . . . . . . . . . . . . . . . . . . . . . . .4-1

Internal Relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1

General Information . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1

Installing the Trigard Gas Monitor

with Internal Relays . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1

Trigard Gas Monitor Internal Relays . . . . . . . . . . . . . .4-2

Relay Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2

Alarm Relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2

Fault Relay or Trouble . . . . . . . . . . . . . . . . . . . . . . . . .4-3

Calibration/RESET Push-button . . . . . . . . . . . . . . . . . . . . . . .4-4

Push-button Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-5

Relay Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-6

Horn Relay Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7

To Activate the Horn Relay . . . . . . . . . . . . . . . . . . . . .4-7

To Reset the Horn Relay . . . . . . . . . . . . . . . . . . . . . . .4-7

Chapter 5,

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1

iv

Chapter 6,

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1

Replacing Trigard Sensor . . . . . . . . . . . . . . . . . . . . . .6-1

Obtaining Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . .6-6

Appendix A,

Optional Features . . . . . . . . . . . . . . . . . . . . . . . .A-1

Strobes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-1

Internal Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-2

Backup Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-2

List of Figures

Figure 1-1. Trigard Gas Monitor . . . . . . . . . . . . . . . . . . . . . . .1-1

Figure 1-2. Circuit Board (3-Wire Version) . . . . . . . . . . . . . . .1-6

Figure 1-3. Three-Wire 4 to 20 mA Operation . . . . . . . . . . . . .1-7

Figure 1-4. Remote Sensor Cable Assemblies . . . . . . . . . . . .1-7

Figure 1-5. General-Purpose Remote Sensor Assemblies . . .1-8

Figure 1-6. Explosion-Proof Remote Sensor Assemblies . . . .1-8

Figure 2-1. LCD Gas Concentration Display . . . . . . . . . . . . . .2-1

Figure 2-3. Ultima Controller . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

Figure 2-2. Ultima Calibrator . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

Figure 2-4. Apply Zero Gas Flag . . . . . . . . . . . . . . . . . . . . . . .2-9

Figure 2-5. Apply SPAN Gas Flag . . . . . . . . . . . . . . . . . . . . .2-10

Figure 2-6. Calibration End Display . . . . . . . . . . . . . . . . . . . .2-11

Figure 3-1. Typical ModBUS Network Topography . . . . . . . . .3-2

Figure 3-2. Typical Communications Wiring Scheme . . . . . . .3-4

Figure 3-3. Sensor Display Screens . . . . . . . . . . . . . . . . . . . .3-6

Figure 3-4. Alarm Status Screen . . . . . . . . . . . . . . . . . . . . . . .3-8

Figure 3-5. ModBus PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-9

FIGURE 4-1. Relay Contacts . . . . . . . . . . . . . . . . . . . . . . . . .4-4

Figure 6-1. "Change Sensor" Scrolls Across the Display . . . .6-1

Figure 6-2. Sensor Assembly and Sensor Guard for General

Purpose Model . . . . . . . . . . . . . . . . . . . . . . . . . . .6-2

Figure A-1. Trigard Gas Monitor with Additional Options . . . .A-1

Figure A-2. Trigard Gas Monitor Power Supply and Battery

Backup Options . . . . . . . . . . . . . . . . . . . . . . . . . .A-2

v

List of Tables

Table 1-1. Power Cable Distances for the Trigard Gas

Monitor with Internal Relays (4-20 mA Model) . . .1-5

Table 1-2. Cable Length and Wire Size

(Power Supply 24 VDC) (Toxic Gas or Oxygen)

Sensor, 4-20 mA Signal Output

(Three Wire Sensor) . . . . . . . . . . . . . . . . . . . . . .1-5

Table 1-3. Remote Module Wiring and Placement . . . . . . . . .1-9

Table 1-4. Remote Sensor Wiring Cable . . . . . . . . . . . . . . . .1-10

Table 1-5. Low Temperature Wiring Cable . . . . . . . . . . . . . .1-10

Table 2-1. Instrument Operation . . . . . . . . . . . . . . . . . . . . . . .2-2

Table 3-1. Maximum Power Cable Length . . . . . . . . . . . . . . .3-3

Table 3-2. Transmitter Power Consumption

(7-30 VDC Supply) . . . . . . . . . . . . . . . . . . . . . . . .3-3

Table 3-3. Remote Sensor Power Consumption

(AC or DC Operation) . . . . . . . . . . . . . . . . . . . . .3-3

Table 3-4. Status Indication Codes . . . . . . . . . . . . . . . . . . . . .3-8

Table 3-5. Supported ModBUS Function Codes . . . . . . . . . .3-11

Table 3-6. ModBUS Memory Map Overview . . . . . . . . . . . . .3-11

Table 3-7. ModBUS Bas Address (Read/Write) . . . . . . . . . .3-12

Table 3-8. ModBUS Factory Configuration Data

(Read Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-13

Table 3-9. ModBUS User Configuration Data (Read/Write) .3-14

Table 3-10. Alarm Function Codes - Word 1(Read/Write at

Address Base+137) . . . . . . . . . . . . . . . . . . . . . .3-15

Table 3-11. Alarm Function Codes - Word 2(Read/Write at

Address Base+138) . . . . . . . . . . . . . . . . . . . . . .3-16

Table 3-12. ModBUS Device Status (Read only) . . . . . . . . .3-17

Table 3-13. ModBUS General Status Bits

(Read Only at address Base+201) . . . . . . . . . .3-19

Table 3-14. ModBUS Fault Status Bits

(Read Only at address Base+202) . . . . . . . . . .3-19

Table 3-15. Control Words (Read/Write) . . . . . . . . . . . . . . . .3-20

Table 3-16. ModBUS Command Word 1 (Read at address

Base+301/Write Coils 1 through 16) . . . . . . . . .3-20

Table 13-17 ModBUS Command Word 2 (Read at address

Base+302/Write Coils 17 through 32) . . . . . . . .3-21

Table 3-18. Sensor Type . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-22

Table 3-19. Sensor Engineering Units . . . . . . . . . . . . . . . . . .3-23

vi

Table 3-20. Information Flags Word #1 –

(Read at address Base+254) . . . . . . . . . . . . . . .3-23

Table 3-21. Information Flags Word #2

(Read at address Base+255) . . . . . . . . . . . . . . .3-24

Table 3-22. Information Flags Word #3

(Read at address Base+26) . . . . . . . . . . . . . . . .3-24

Table 3-23. Information Flags Word #4

(Read at address Base+257) . . . . . . . . . . . . . . .3-25

Table 3-24. Alternate Gas Readings (Read/Write

at address Base+258 to Base+260) . . . . . . . . .3-25

Table 4-1. Relay Specifications . . . . . . . . . . . . . . . . . . . . . . . .4-2

Table 4-2. Push-button Calibration . . . . . . . . . . . . . . . . . . . . .4-5

Table 5-1. Performance Specifications . . . . . . . . . . . . . . . . . .5-1

Table 5-2. Sensor Response to Interferants . . . . . . . . . . . . . .5-4

Table 6-1. Operational Display Messages . . . . . . . . . . . . . . . .6-3

Table 6-2. Configuration Display Messages . . . . . . . . . . . . . .6-4

Table 6-3. Troubleshooting Guidelines . . . . . . . . . . . . . . . . . .6-5

Table 6-4. Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . .6-6

vii

Chapter 1,

Installation

General Description

The Trigard Gas Monitor is designed to sample the environment where

mounted and alert you to potentially dangerous levels of your target

gas, depending on your particular model. The unit is factory-calibrated

and shipped ready for installation.

Identifying Your Unit

• The Trigard Gas Monitor is housed in a rugged, plastic general-

purpose enclosure (FIGURE 1-1).

• The Trigard Gas Monitor comes standard with internal relays, a

Cal/Reset pushbutton, and a 95 dB horn. See Chapter 4 for details.

• The gas sensor type and range are located on the sensor module

label. Unscrew the sensor assembly to view the label.

Any options ordered, such as Strobes, Battery Backup or Internal AC

Power Supply, will be included.

Figure 1-1. TRIGARD Gas Monitor

1-1

Installing Your Gas Monitor

NOTE: Reference installation outline drawings listed in Chapter 3,

"Specifications".

Generally, the Trigard Gas Monitors or remote sensing module should

be mounted close to the area where a leak is likely to occur or where

the gas is expected. Install the Trigard Gas Monitors or the remote

sensor at a high level (ceiling) or low level (floor), depending on the

density of the gas most likely to be found. Install the unit so that the

front display is not blocked or hidden from view.

Mount the Trigard Gas Monitor or remote sensor with the

sensor inlet fitting (FIGURE 1-1) pointed downward; other-

wise, the inlet may become clogged with particulate matter

or liquids.

Do not paint the Trigard Gas Monitors. If painting is done in

an area where a sensor is located, exercise CAUTION to

ensure paint is not deposited on the sensor inlet fitting.

Such paint deposits would interfere with the diffusion

process, whereby a sample of the monitored atmosphere

diffuses into the sensor. In addition, solvents in the paint

may cause an alarm condition to occur.

Protect the Trigard Gas Monitors from extreme vibration. Do

not mount sensing head in direct sunlight as this may cause

overheating of the sensor.

Do not locate the general-purpose enclosure models in an

area which may contain a flammable mixture of gas and air;

otherwise, an explosion may occur. The general-purpose

Trigard Gas Monitors can be a source of ignition and must

not be mounted in an area where a flammable mixture of

combustible gas and air may become present.

"

WARNING

"

WARNING

1-2

Installing the Trigard Gas Monitor

Remove lid and drill enclosure for power, signal and optional relay cable

entry. Use one of the following methods to mount the general-purpose

Trigard Gas Monitor.

• Using customer-installed wiring holes, install the Trigard Gas

Monitor to the end of rigid conduit.

• Use mounting holes in the corners of the Trigard enclosure to

mount directly to a wall.

Electrical Connections for Trigard Gas Monitors

Before wiring the Trigard Gas Monitors, disconnect power

source supplying the monitor; otherwise, electrical shock

could occur.

NOTE: For information on internal relays, see Chapter 4.

For Trigard units with ModBUS, see Chapter 3.

This three-wire assembly is marked to identify power, ground and signal

connections for all combustible, toxic, and oxygen models.

Wiring

Install wiring in accordance with the electrical code of the country in use

and UL 61010-A1 or CSA C22.2 No. 1010.1, as applicable. In these

installations, twisted-pair, instrument quality cable is recommended.

Shielded cable is recommended for cable runs where interferences from

radio frequency interference (RFI), electromagnetic interference (EMI)

or other noise sources exist (such as motors, welding equipment,

heaters, etc.).

NOTE: See Installation Outline Drawings for wiring details.

Conduit may also be needed in areas where large amounts of electrical

noise is expected.

Use caution when selecting a cable size. TABLES 1-1 and 1-2 express

the maximum cable length when only using the Trigard Gas Monitors.

Trigard options may take additional power which requires a heavier

cable or a short cable run.

"

WARNING

1-3

When selecting cable size, consider future needs (i.e., addition of

sensors and/or options available with the Trigard Monitors). See

Chapter 3, "Specifications" for proper input voltage.

Ensure that water and dirt are not able to enter the unit via the wire or

conduit. If the unit is installed in a location known to be wet or damp, it

is good practice to loop or bend the entry into the unit that prevents

water incursion.

For Milliamp Output

The Trigard Gas Monitor (three-wire version) may be connected to any

device capable of accepting 4 to 20 mA analog signals such as:

• Model 9010/9020 Controller

• GasGard XL Controller

• Programmable controllers

• DCS’s, etc.

An external power supply is needed if the optional internal power supply

is not ordered. (For power requirements, see Chapter 3,

"Specifications".) All connections should be made by following

appropriate wire code procedures.

• See TABLES 1-1 through 1-2 for typical cable length and wire size

for installation.

When using any of the the Trigard accessories (such as

relays) with the 4 to 20 mA output Trigard Gas Monitor, a

three-wire connection must be used. Failure to use a three-

wire connection could damage the electronics within the

Trigard Gas Monitor which can result in serious personal

injury or death.

Be sure to install your Trigard Gas Monitor according to National

Electrical and local procedural codes. Failure to do so can result in an

unsafe condition.

NOTE: See Chapter 3 for ModBUS output.

"

WARNING

1-4

Table 1-1.

Power Cable Distances for the Trigard Gas Monitor with Internal

Relays (4-20 mA Model)

SENSOR TYPE POWER WIRE SIZE MAXIMUM MAXIMUM LOAD

SUPPLY CABLE RESISTANCE

VOLTAGE LENGTH (mA OUTPUT

(IN FEET) ONLY)

CATALYTIC

COMBUSTIBLE 12 VDC 16 AWG 900 300 OHMS

CATALYTIC

COMBUSTIBLE 24 VDC 16 AWG 3000 600 OHMS

TOXIC OR OXYGEN 12 VDC 16 AWG 2500 300 OHMS

TOXIC OR OXYGEN 24 VDC 16 AWG 8000 600 OHMS

• See TABLE 1-6 for remote sensor distances.

• In all installations, twisted instrument-quality cable is

recommended.

• Shielded cable is recommended in situations where radio

frequency interference (RFI), electro-magnetic interference (EMI)

or other electrical noise sources exist or are anticipated.

Typical Trigard Gas Monitor Wiring

Table 1-2.

Cable Length and Wire Size (Power Supply 24 VDC)

(Toxic Gas or Oxygen) Sensor,

4-20 mA Signal Output (Three Wire Sensor)

WIRE SIZE MAXIMUM CABLE LENGTH IN FEET MAXIMUM LOAD RESISTANCE

22 AWG 12,000 600 Ohms

• Three-wire Trigard Monitors operate in the current source mode

(see FIGURE 1-3).

1. Identify the main pc board:

• It is the round pc board, located inside the lid assembly.

1-5

2. Connect 8 to 30 VDC power lead to J8-1 (see FIGURE 1-2).

3. Connect J8-2 to 4 to 20 mA input on remote system.

4. Connect the signal ground to J8-3.

5. Connect the sensor module to labeled connector J-1 on the main

pc board.

6. Wire for relays (see Chapter 4).

7. Assemble lid on enclosure.

Figure 1-2. Circuit Board (3-Wire Version)

1-6

Installing the Trigard Remote Sensor Module

The Remote Sensor Modules are available in a variety of options.

Pre-wired general-purpose sensors are available in lengths of 25, 50 or

100 feet. These remote sensors are not housed in an enclosure, which

makes it easier to mount in small places.

Figure 1-4. Remote Sensor Cable Assemblies

Figure 1-3. Three-Wire 4 to 20 mA Operation

1-7

Remote sensors can be ordered with general purpose (GP) remote

sensor assemblies.

Remote sensors can also be ordered with explosion-proof (XP) remote

sensor assemblies.

Figure 1-6. Explosion-Proof Remote Sensor Assemblies

Figure 1-5. General-Purpose Remote Sensor Assemblies

1-8

The GP or XP Remote Sensor Modules can be mounted in a manner

similar to the gas monitor installation in the preceding procedure and at

a maximum distance outlined in TABLE 1-3.

Table 1-3. Remote Module Wiring and Placement

GAS TYPE MINIMUM WIRE SIZE MAXIMUM DISTANCE

Toxic and Oxygen 20 AWG 100 FEET

Catalytic Combustible 18 AWG 50 FEET

16 AWG 100 FEET

IR Combustible 16 AWG 50 FEET

12 AWG 100 FEET

Permanently connect 1/4" ID tubing to the post on the windguard. Route

this tubing to the Trigard Gas Monitor, ensuring that there are no kinks,

leaks or other obstructions. Secure this tubing near the monitor; it is

used to deliver check gas to the sensor module during calibration.

Tubing used for reactive gases (Cl

2

, HCl, ClO

2

, HF, NH

3

,

ETO, F

2

, B

2

H

6

, Br) should be as short as possible (18 inch-

es maximum) to ensure that the gas reaches the sensor.

Excessive tubing can result in no gas sensor reading.

Electrical Connections for the Trigard Remote

Sensor Module

Before wiring the Trigard Remote Sensor Module, discon-

nect the power source feeding the Remote Sensor Module

and the Trigard Gas Monitor/Less Sensor; otherwise, electri-

cal shock could occur.

When installing Trigard Remote Sensor Module with its mat-

ing Trigard Gas Monitor/Less Sensor, follow National

Electrical and local procedural Codes; failure to do so can

result in an unsafe condition.

Five conductors are required for the Trigard Remote Sensor Module.

The Trigard Monitor has a five-wire terminal to accommodate up to #16

AWG conductors.

"

CAUTION

"

WARNING

"

CAUTION

1-9

Some installations require metal pipe or metallic conduit. In these

cases, separate conductors or unshielded cable may be used.

For open wiring, shielded wire or cable should be used to minimize the

possibility of noise interference and contact with other voltages.

Selection of this shielded cable must comply with local requirements.

TABLE 1-4 shows suggested cables for Trigard installations; other

cables are available which are also adequate.

Table 1-4. Remote Sensor Wiring Cable

SUPPLIER CATALOG NUMBER DESCRIPTION

ALPHA WIRE CORP. 5525 5 cond., shielded, 18 AWG

5535 5 cond., shielded, 16 AWG

5514 4 cond., shielded, 20 AWG

Table 1-5. Low Temperature Wiring Cable

SUPPLIER CATALOG NUMBER DESCRIPTION

ALPHA WIRE CORP. 45525 5 cond., shielded, 18 AWG

45366 6 cond., shielded, 16 AWG

45545 5 cond., shielded, 14 AWG

At the Trigard Remote Sensor Location:

1. Open the Trigard Remote Sensor cover by removing lid.

2. Route the cable from the Gas Monitor through a customer-supplied

opening in the enclosure and wire it to the terminal block

(FIGURE 1-2).

3. Verify the identity of each conductor of the cable and connect the

wire to the terminal block.

4. Re-install the cover of the Trigard Remote Sensor

NOTES:

• Incoming power and signal cable shield should be earth grounded

at the power source. Connect power and remote sensor cable

shields to shield terminals on main pc board. Provide shield

terminations inside the sensor housing as indicated on Installation

Outline Drawings for Remote Sensor; see Table 5-1 for Installation

Outline Drawing document numbers.

• Cables larger than #16 AWG will require a splice of smaller cable

to fit the connector.

1-10

Chapter 2,

Start-up and Calibration

for 4-20 mA Output

Initial Start-up

• The Trigard Gas Monitors are factory-calibrated. A bump check

prior to use is recommended.

• Once power is applied to the unit, the LCD shows a test of all

display words. The software version number displays; then, a 30-

second (self-check) countdown for sensor stability begins.

• During the 30-second countdown, the output signal is the same as

the calibration signal when enabled during a normal calibration.

This is described later in this chapter under "Trigard Gas Monitor

Calibration Output Signal".

• The Alert red LED will be solid ON during the 30-second

countdown.

• After the 30-second countdown, observe that the gas type

and gas concentration (ppm, % Gas, or % LEL) alternately flash

(FIGURE 2-1).

1).

• The Normal green LED will be solid ON after the 30-second

countdown.

• A complete listing of instrument operation features can be found in

TABLE 2-1.

Figure 2-1. LCD Gas Concentration Display

2-1

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MSA TRIGARD® Gas Monitoring System Owner's manual

MSA TRIGARD® Gas Monitoring System Owner's manual

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