904/745 Series

Digital Step Controller / Sequencer

The 904 and 745 Controllers have identical functions except that the 904 adds a pulse width modulated output signal to control a continuously variable power switch(such as 905 Series) or motor, thereby providing a continuous range of output power based on the input signal.

The 904 and the 745 Series Sequencers accept 2-10 VDC and 0-20 mA input signals and sequence up to 14 stages of isolated pilot duty relays in order to match the demand.

The 904 and 745 Series Sequencers feature an optional on board thermostat step point with a remote temperature sensor for dedicated heating or cooling applications. The 906 Series Thermostats can provide the signal to drive these sequencers.

Also available is a PI function which serves to modulate the output as required in order to drive a sensor signal (temperature, flow, pressure) to match the set point.
Stacks Image 1133
  • Compressors or unloaders
  • Pumps
  • Blowers
  • Fans
  • Boilers
  • Electric heating elements
  • N.O. isolated relay outputs
  • LIFO or FIFO operation
  • Adjustable stage delay
  • LED indicator for each stage
  • Adjustable integration time of PI function
Data Sheets and Instructions