Carrier SUPRA 950Mt - Relay Operation

3-8
850 Mt
/
950
Mt
a.
CPL By
pass V
alve
The valve is controlled by the micro (P2).The valve
opens and closes at the values chosen by FN6.
See Table 1--4 “Bypass Valve Setup”.
The
va
lv
e
is
en
erg
is
ed
du
rin
g
pu
ll-
-do
wn
if
the
suction pressure is below the value chosen by FN6
(default = 1.17 bars). If the pressure rises above the
value chosen by FN6 (default = 1.72 bars) the valve is
de-
-ener
gis
ed.
The
val
ve
is
de-
-energ
ise
d
dur
ing
regul
ation (in low
speed heat and cool and
null -
-
See
figures 2--14 to 2--17).
3.
5.
5
Re
la
y
op
er
at
io
n
D
Engine
mode
Automati
c start
:
Run relay is energized via W1 output.
Diesel/Electric relay is energized via N2 output :
-
-
Run/sto
p solen
oid is acti
vated in R
UN posi-
tion. Fuel pump is energized.
-
-
Vol
tage sup
ply to stand
by motor con
tactor
and subsequent motor start is prevented.
Glo
w
pl
ug
s
ar
e
en
erg
iz
edvia
GPRrela
y
(T3outp
ut)
.
Th
en
sta
rte
r
so
le
no
id
is
en
erg
iz
ed
vi
a
SSR
re
la
y
an
d
T2 output. Engine will crank for 10 seconds or until
eng
ine
ope
rati
on
is
sen
sed
by
the
alte
rna
tor
sig
nal
(L3
).
GPR
is
de-
ene
rgi
zed after
the
aux
ili
ary
inp
ut
is
sensed on. If engine does not start a 15 seconds null
period will elapse before next start attempt. Run relay
(RR) is kept energized.
D
Standby
mode
Automa
tic start
:
DER relay is energized via N2 output.
-
-
Prevents a
ctivatio
n of engin
e run sol
enoid
and fuel pump.
-
-
Standby
motor co
ntactor is
energi
zed.
RR is energized. Electrical power is supplied to the
standby motor for starting.