Electra Emd 50 - Heaters Operation Rules for RC and SH Groups; Operation Rules for Heaters in RC Group; Rules for Heaters Operation in SH Group

7-13
CONTROL SYSTEM
Revision Y05-01Service Manual - EMD Series
4.1.2 Heaters operation rules for RC and SH groups
(a) For both RC and SH groups, Heaters versus T is as the following:
OFF
ON
ON
OFF
HE1
HE2
1 2 3 4
T=SP-RT [
o
c]
(b) Operation rules for Heaters in RC group:
(i) Heaters can be enabled only if IFAN is ON.
(ii) Heaters will operate according to T and the following graph:
32
20
20
15
50
ON
OFF
ICT
45
HE-1
&
HE- 2
General:
Window:
(c) Rules for Heaters operation in SH group:
(i) When heaters are to be ON and IFAN is to be OFF according to 4.1.2 (a), IFAN will be
forced to low speed.
(ii) Heaters will operate according to T and the following graph:
(d) F
o
r
b
o
t
h
RC and SH groups, excluding deicing, HE1 and HE2 can be on only when the compressor is on.
50
ON
OFF
ICT
45
HE - 2
37 42
HE -1
ON
OFF