CPC (UK)

Technical Overview

Operation

Upon power up the green healthy LED will flash whilst the sensor warms up. After 60 seconds the healthy LED will switch on permanently to indicate the SP-ir is fully operational. If the refrigerant concentration rises above the alarm threshold the healthy LED switch OFF and the Alarm LED will slowly flash red until the alarm delay time has expired after which it will be permanently lit, the audible alarm will be initiated and the alarm relay will change state. If setup for dual alarm thresholds, and the refrigerant concentration continues to rise, once the critical alarm threshold is exceeded the Alarm LED will flash red at a fast rate and the critical alarm relay will change state. A mute button is fitted to the front cover of the detector to silence the audible alarm or if not easily accessible can be silenced via an remote mute button which is connected to the digital input on the detector.

Operating Range

Detectors can operate in either a single or dual alarm threshold mode (Alarm & Critical Alarm), selectable using bit switches.

Sensors are available for various ranges, depending on the target gas type and the desired application;

• HFC sensors: 0-2000ppm
• HFO sensors: 0-2000ppm or 0-100%LEL
• Co2: 0-10000ppm or 0-20000ppm
• Hydrocarbons: 0-100%LEL

Alarm thresholds can be defined automatically according to the bit switch configuration or alternatively custom alarm thresholds can be configured via the network connection or using the Site Assistant Android App.

Alarm Configuration

Bit switches are used to select single or dual alarm threshold modes and also to select preset alarm thresholds, alternatively a network connection will allow custom alarm threshold values to be used. The alarm time out delay is also selected using bit switches with 0, 1 minute, 5 minutes or 30 minutes options available or custom configured via the network connection or Android App. Two bit switches are provided to enable the user to select failsafe/non failsafe operation of both the alarm and fault relays. A final pair of bit switches are used to configure if the alarm relays latch or do not latch following an alarm clearing.

Self Test

Depressing the reset button, or activating the reset digital input for 2 seconds (during normal healthy operating conditions) will initiate a 10 second self test cycle. The two relays change to alarm/fault condition, the LED indicators and buzzer will switch ON, after which normal operation is resumed. Self test initiation maybe logged by remote systems via the network connection.

Analogue Outputs

A optional and voltage or current output can be provided to interface with third party equipment. The output type can be selected, and will indicate the unit status and current gas reading, for example :-

0 to 20 mA -

• 2 mA - Detector fault
• 3 mA - Detector in warm up mode
• 4 to 20 mA - Linear across PPM range

Remote or local sensor option

Remote or locally mounted sensor versions are available. Remote sensors can be supplied with 3M to 15M cable lengths and wall mounting enclosure.

Remote Communications

An RS 485 serial interface or optional Ethernet interface enables communications between the detector and building management systems. Using the Modbus RTU protocol enables the following data to be viewed/changed :-

• PPM concentration
• Alarm threshold levels and alarm time delay
• Unit status (Normal, Warmup, Alarms etc..)
• Relay status and configuration
• Refrigerant type and sensor range
• Self test status