Features

Microprocessor based Addressable modules

Discrete 4-20mA output

Three (3) Programmable alarm relays

RS-485 MODBUS RTU Serial Communication

PLC and SCADA Compatibility

Alarm Status LED Indicators

External Explosion proof Alarm Reset switch

Description

Model PT900-6XP is a microprocessor based modular controller suitable for use in Hazardous locations. Maximum of six (6) PT900 Series toxic or combustible gas control module can be interfaced with Pem-Tech’s gas sensors. The control modules provide digital display, discrete 4-20mA analog output and programmable alarm relay contacts.

The low power RISC based microprocessor allows all the alarm levels and control module address programmed via switches on the front panel. The bright LED display indicates the gas concentration. Also features amber and red LED indicators for alarm status. One of the safety features is a flashing digital display when the control module is in alarm bypass mode. The flashing display is an indication to the personnel in the control room about the alarm bypass status.

Each control module has RS-485 MODBUS RTU serial communication compatible with PLC’s, SCADA, and DCS systems. The module provides complete status like current gas concentration, sensor calibration and current alarm status. The alarm levels can also be accessed and programmed via MODBUS.

Specifications

Electrical Classification

Explosion Proof, suitable for use in Hazardous Locations

Front Panel Indicators

2 Bright LED digital display

4 each Alarm LED Indicators

Flashing digital display if module in alarm bypass mode.

Test & Safety Features

Displays programmed alarm levels and alarm with flashing alarm LED indicators at unit power up to check the integrity of display and LED indicators

Operating Temperature

-40°F to +158°F (-40°C to +70°C)

Operating Humidity

5% to 100% RH, non-condensing

Mechanical Specifications

Height: 22 inches (158 mm)

Width: 17 inches (432 mm)

Depth: 11 inches (279 mm)

Weight 110 Lbs. (50 Kg)

Approvals

Enclosure: CSA & UL

Control Modules: ABS Type approved

ABS Rules: 1-1-4/3.7, 4-8-3/tbl 2 4-8-3/1.7

Input Power

14-28 VDC. 24 VDC nominal

Power Consumption

Per channel 160mA @ 24 VDC including gas sensor and control module

Alarm Relays

Low, High & High-High alarm relays.

Fully programmable zero to full scale range. Latching or non-latching

Relay Ratings

SPDT Form “C” type Relay contacts

5 Amps @ 250 VAC or 30 VDC

Auxiliary Alarm Relay Assembly (Optional)

Four (4) each alarm relay contacts

Each relay rated 10Amps @ 125 VAC /
28 VDC

Analog Output

Discrete 4-20mA (300 Ohms max. load) 2.0 mA - When sensor in Calibration mode

< 1.0 mA - Sensor malfunction

Peripheral & Interface

RS-485 MODBUS RTU Compatible with PLC’s, SCADA and DCS systems.

Annunciator model PT750 for remote