FiOC-40 is a panel controller that controls equipment such as air handling units, pump sets, boilers and chillers and decides in what order they come on. The control logic runs on the device; sensors and field equipment are wired straight to its terminals. Below is a summary of which channel type each signal in a typical AHU panel goes to.
Temperature, humidity and pressure: UI inputs
- Temperature sensors: common NTC types, PT1000 and NI1000. Two wires, no polarity.
- Humidity, pressure and similar transmitters: transmitters with a 0–10 V, 2–10 V, 0–20 mA or 4–20 mA output.
The device notices a broken or shorted temperature sensor. With 4–20 mA and 2–10 V signals a broken cable is also reported as a fault; with 0–10 V and 0–20 mA a break cannot be told apart. The device does not power a 4–20 mA transmitter; the transmitter needs its own supply.
Valve and damper actuators: FIO outputs
Modulating valve and damper actuators connect to the FIO channels as a 0–10 V or 2–10 V analogue output. The FIO only provides the control signal; the actuator’s own supply comes from a separate 24 VAC source.
Fan and pump start: DO relays
Fan and pump contactors are driven by the dry-contact relays on the DO channels. A suppressor on the contactor coil is recommended. The digital output of an FIO channel is not a relay; to switch a load, a relay is placed in between.
Filter, thermal trip and flow contacts: DI inputs
Status and fault contacts such as dirty filter, thermal trip or flow present are wired as dry contacts to the DI inputs. If you run out of digital inputs, UI and FIO channels can also be set as digital inputs.
At power-up
When the device starts, relay outputs are released and analogue outputs sit at their minimum until the application writes its first command. Field equipment should be chosen so that the plant also stays safe in that state.
If 40 points are not enough, the extra points come from FiO-40 modules while the control logic stays on the FiOC-40.
Detailed technical values are given in the product datasheet; our dealers can assist you with your project.