Page 59
CBX32MV
I
ECB40‐20CB, ECB25CB - 208/230V Three Phase
FIRST-STAGE HEAT
1.
W1 of the thermostat provides a W1 demand to the Control. The Control outputs a 22VDC signal to the K32 and K34 relays.
K32-1 and K34-1 closes.
2.
Assuming the N.C. primary (S15) and secondary (S20) limit switches are closed, electric heat elements HE1 and HE2 are
energized.
SECOND-STAGE HEAT (remove jumper between W2 and R)
1.
When K34 closes, the unit is ready for a second stage heat demand. W2 of the thermostat provides a W2 demand to the
Control. The Control outputs a 22VDC signal to the K33 and K35 relays. When K33-1 and K35-1 closes and assuming
the N.C. primary (S15) and secondary (S20) limit switches are closed, electric heat elements HE3 and HE4 are
energized.
1
3
4
2
1
2
3
3
3
3
3
4
4
1
1