Siemens SQN72 Series - Circuit Diagrams and Control Sequences (LOA;LMO); LOA;LMO 2-Stage Operation (Low-Fire)

14/20
Smart Infrastructure CC1N7802en
8/11/2021
Circuit diagrams (examples)
No. B  LOA24 / LOA25 / LOA26 / LOA28 / LOA36 / LMO24 / LMO44
2-stage operation  prepurging at low-fire position (KL)
1)
Without oil preheater
2) With oil preheater:
If the oil preheater contact
(OW) opens during operation, a
restart follows
*) Thermostat or similar unit with
NO contact (1
-
wire control)
X1
Plug
-
in space, 4
-
pole
X2
Plug
-
in space, 5
-
pole
I
II
III
IV
red
blue
orange
black
4)
One-sided approach to the
target position to eliminate the
switching differential (backlash
compensation).