M-Controller

The M-Controller is a multi-channel controller and alarm unit that utilizes both digital and analog communications to interface with a maximum of 32 remote digital QEL transmitter/sensors, and 8 analog transmitter/sensors. These are used to measure a wide variety of toxic gases such as CO, NO2, NH3, H2S, SO2, Refrigerants, Combustibles, and CO2.

The RS-485 communication is connected via a 4-wire multidrop configuration to reduce the overall installation costs of the system. Range and alarm set points are set through the front keypad or through QEL supplied software that is downloaded to the controller from a PC or laptop computer.

With three standard on-board relays the controller can direct up to 12 remote relay modules, each of which may have up to eight relays for a total count of 99 relays, without compromising the sensor count. Common relay configurations include voting, averaging, delay on actuation and deactuation, normally/not-normally energized and latching.

The audible alarm has three buzzer settings, continuous, intermittent and double-tap intermittent. An additional feature includes 24 VDC transistor outputs for a horn and strobe. An RS-422 responds as a RTU Slave using MODBUS protocol which allows the controller to provide read status information only. The RS-232 interface uses a RJ-11 telephone jack primarily used for uploading and downloading a large configuration database. Available is an analog output card that includes eight 4-20 mA analog outputs. Each analog output can be defined in complex fashions allowing the averaging of several input signals and the assignment of different values to both the 4 and 20 mA outputs. The M-Controller automatically linearizes the values between these two points. Each controller comes standard with a 2 x 16 character back-lit display with an adjustable scroll rate.