CM-2 - Microprocessor Based Temperature Control System

The Problem

Finding a way to maintain both operational and monitoring control of an electric heat trace system.

A need for quick and easy identification of problems throughout all parts of the system.

Constantly increasing expense for manpower in operation and maintenance.

Solution

A scanning microprocessor-based control system that controls and monitors any possible functional area of a heat trace system:

High and low temperature limit alarms • Power and circuit failure
Sensor, memory and communications failure • Problem diagnosis.

Capabilities

Located in the plant for local access by plant personnel
Linked to a master unit
Connected to the plant process control computer.
Factory programmed, eliminating need to initialize system in the field.
Configured in a 40 circuit versions (CM-2-40).

The CM-2 is also very easy to use:

Large two-line display gives information in common English; no cryptic computer codes to interpret.
Self-calibration and group programming dramatically shortens setup and maintenance time.

Because of its superior monitoring and control capability, CM-2 installations see dramatic reduction in operational and maintenance costs due to:

Centralized location for testing and control maintenance.
Quick, simple switching from one batch process to another.
Reduced service time by providing quicker analysis and problem identification.

Features

GENERAL FEATURES:

NEMA 4, 4x, 12 enclosures
Wide Operating Range: -40°F to + 130°F ambient
Conformal coated circuit boards with gold plated connectors
Noise and transient immunity from software filters and time delays
No memory loss during power outages; has non- volatile memory
Communications port available for RS-485
FM and CSA certified for Class 1, Division 2, Groups A, B, C and D

SPECIFIC CM-2 FEATURES

Programmable temperature control set point and dead band
Programmable hi & low temperature alarms
Actual pipe temperature read out
Block programming - can set large number of settings quickly
Easy to read, two line, twenty character displays, gives prompts in English - no codes
Multiple set point storage allows quick switching between different product processes
Smart remote - can function alone or can be connected to central unit or process computer
Security codes allow different levels of access by personnel from any system location
Self checking and calibrating system
Sensor failure alarms
Second reflash capability
Inputs 100 ohm (DIN) RTD or Type J thermocouple
Power, communications, and memory alarms
Manual override capability

Specifications

40 channel microprocessor based system with temperature control and system monitoring, mounted in a NEMA ___ (12, 4, 4X) cabinet. Unit shall be failsafe, include a self calibrating feature, large two line twenty character display and security codes to control access. Power switching relays shall be rated to handle ____ (120, 240, 277, 480).

Temperature control features must be selectable per channel and include: maintain temperature, low temperature alarm, high temperature alarm, deadband of control, failure mode (heater on or off), circuit active or off, and Centigrade or Fahrenheit display units . Temperature sensor inputs must be three wire 100 ohm RTD or type J thermocouple inputs and be field selectable. Up to four different programs must be able to be stored to allow rapid variable change for different chemical processes.

Heater monitoring features must include adjustable ground fault alarm, adjustable ground fault trip, deactivation of ground fault trip, heater current, loss of voltage, low heater current alarm, and high heater current alarm. Unit shall be equipped with an adjustable auto test cycle to periodically turn heaters on and verify their performance.

Controllers shall have communications capability- shall utilize Modbus protocols for communicating with other systems. The controller must also communicate with PC host communications software. The PC communications software shall include the ability to monitor each channel’s status and alarms. Controller settings must be able to be changed from the PC host software.