Four Channel Digital Input Multiplexer – VFC input




The Digital  Input  Expander allows 4 volt free inputs to be monitored by a single analogue input  channel. The resultant analogue value can be decoded by the A to D function module in an BMS controller to produce internal digital status bits for alarm monitoring or other status input applications.



Supply Voltage:          24Vdc or ac ± 15%

Supply Current:          50mA max. (I mode)

 30mA max. (V mode)

Input Channels:           4-volt free contact switch 24Vdc

Input Threshold:         Upper 17.5V max (ON) level

  Lower 7.5V min (OFF) level

Distance:                          Max. distance of IOD4 from controller 25m (V mode)

  1000m (I mode).

Output:                              Mode selectable by link header current/voltage (I/V).

I:                                              0 to 20mA, max. resistance of load 250Ω.

V:                                            0 to 10Vdc, max. current 1mA.

LED:                                      Single LED per input channel, LED on indicates contact


Ambient limits:             Storage: -10℃ (14 °F) to +70℃(158 °F)

   Operating: -10℃ to +50℃

   Humidity: 0 to 90%RH non- condensing

Weight 81 g
Specification Guide