The VT7225 controllers are microcomputer-based, proportional and integral (PI) devices with one analog 0 to 10 VDC output, one 8 VDC and one 24 VAC proportioning pulsed output. The analog 0 to 10 VDC modulating output can control the room or supply temperature by modulating directly a 0 to 10 VDC SCR power controller. The VDC and VAC pulsed outputs can control the room or supply temperature by modulating directly 4-32 VDC triggered solid state relays (SSR’s) using a time proportioning control algorithm on a 1 second time cycle.
- 0 to 10 VDC modulating output
- VDC pulsed modulating output
- VAC pulsed modulating output
- Night setback digital input
- Room or supply control applications