HONEYWELL 05701-A-0550 Single channel control card

The 5701 Single Channel Control Card provides control, display and alarm facilities for a connected gas detector. The front panel display indicates the gas reading and channel status

while LEDs are used for alarms. A push-button is provided for resetting the alarms and selecting the card for use with the Engineering Card.

The operation of the control card is microprocessor controlled and is fully definable for a wide range of connected gas detectors and application requirements. The softwareconfiguration setup is stored in an EEPROM.

There are two types of control card depending on the type of gas detector being fitted to the system:

a. Single Channel Control Card 4 - 20mA.Part Number 05701-A-0301.

b. Single Channel Control Card Catalytic.Part Number 05701-A-0302.Each of the above control cards consist of a single channel control card fitted with the respective plug-in sensor drive module.An optional Analogue Output Module can also be plugged into the single channel control card to provide a remote output of the channel card readings.

The Single Channel Control Card carries out the control functions for a single loop of gas detection as follows: 

a. Processes the incoming sensor drive module signal.

 b. Displays the signal level on the front panel liquid crystal display. 

c. Compares the signal level with pre-defined alarm limits. 

d. When the pre-defined alarm limits are exceeded, raises the alarms by lighting up front panel LEDs and operating optional connected relays. 

e. Informs other cards with the alarm status information. 

f. Self validates the operation of its circuit components, software operation and the condition of the sensor. 

4.3 Sensor Drive Modules Two sensor drive modules are provided: 

a. Sensor Drive Module, 4 - 20mA, Part Number 05701-A-0283 

b. Sensor Drive Module Catalytic, Part Number 05701-A-0284 The Sensor Drive Module conditions the incoming catalytic or 4 - 20mA sensor signal and provides the necessary sensor power supply. 

It contains all the circuitry necessary to generate the voltages and currents required to drive the sensor, the circuitry to acquire the sensor signal and to scale the sensor signal to a standard output. The sensor drive modules are factory fitted and plug directly onto the channel control card. 

4.4 Analogue Output Module An optional Analogue Output Module, (Part Number 05701-A-0285), may be factory fitted to the Single Channel Control Card and is used on a channel of gas detection to provide an isolated current loop output which follows the sensor signal level. This may be set electronically to produce a 0 - 20mA output or a 4 - 20mA output and can be used to operate a chart recorder, etc.

The physical layout of the Single Channel Control Card is shown below. The Sensor Drive Modules plug into the 14-way connectors J1 and J2 while the Analogue Output Module, when fitted, plugs into J3 and J4. Link LK1, available on MkII cards only, is used when individually powering control cards See Chapter 4, Section 16.2.

The Engineering Card (Part Number 05701-A-0361) is used on a System 57 rack to provide a common interface that enables the user to perform all the required functions to commission and operate each fitted control card. f. Self validation of the operation of its circuit components, software operation and the backplane communications. The front panel is fitted with a series of tactile push-buttons for the operation of various functions, LEDs to provide rack power and communications status and a mini DIN socket for the connection of a serial printer, computer or an engineering key. The Engineering Key is used to unlock functions that can alter the operation of a control card. The Engineering Card is always fitted into the right-hand slot of the rack and provides: a. Routeing of the 24V dc input from the DC Input Card to the backplane of the rack. b. A backplane serial communications controller and monitor. c. A time and date reference. d. An RS232 external engineering interface. e. Depending upon the security level, the operation of the following rack facilities: Catalytic sensor head current monitoring and adjustment. Alarm set point checking, adjustment and testing. Sensor signal zero adjustment. Sensor signal span adjustment and setting of sensor life monitoring values. Sensor line monitoring. Enabling of control card alarm inhibit. Checking and adjustment of the system clock

One of four optional modules may be fitted to the Engineering Card: a. Master Alarm Update Module This facility provides an indication when a new alarm occurs on any channel in the rack, even if a previous alarm condition already exists. b. Event Printing Module This facility provides time stamped reporting of alarm and fault events as they occur and system status at predetermined regular intervals. c. Modbus Interface Module RS422/485 This facility provides for digital communication between the System 57 Control System and an external computer system using the RS422/485 serial data format and the Modbus communication protocol. d. Modbus Interface Module RS232 This facility provides for digital communication between the System 57 Control System and an external computer system using the RS232 serial data format and the Modbus communication protocol.

The dc power to the rack normally enters the sub-rack via the DC Input Card (Part Number 05701-A-0325). This power may be supplied by the user from an external nominal 24V dc supply. The dc supply is routed through the Engineering Card and sub-rack back plane to all cards in the rack and is protected by a fuse on the DC Input Card. There is a two part terminal block, TB1, to aid removal of the card without disconnecting each of the connected wires. If required, a stand-by backup battery supply may also be connected to the auxiliary dc input connections. The PSU and AUX connections are isolated from each other by diodes. The DC Input Card also provides RFI filtering and reverse polarity protection.