22
AGL_Unit_LOCU_EN_Rev00
NOTE: The SB1 button (test button) allows to by-pass the low-pressure device B10. It might
be useful under certain system conditions to manually let the compressors run. Only qualified
and trained technicians should activate the compressors manually. Keep system pressures
and temperatures within acceptable limits.
Three LEDs (P1/P2/P3) show the status during rescue mode:
▪
P1 green = Cooling demand, compressors run according to S1 & S2 activation
▪
P1 red
= Indicates that the system is in emergency mode
▪
P2 green = Compressor 1 discharge temp, oil level & overload status "OK"
▪
P2 red
= Compressor 1 >> High-pressure cut-out
▪
P3 green = Compressor 2 discharge temp, oil level & overload status "OK"
▪
P3 red
= Compressor 2 >> High-pressure cut-out
2.15.2 PS1
– Setpoint adjustment of low-pressure switch in rescue mode
A pressure limiter is installed f or low-pressure protection. This device is designed according to
EN 12263. It has an automatic reset.
In emergency mode, PS1 takes over the control of the suction pressure regulation. It should be
adjusted on a case-by-case basis per application requirements. The f actory settings of the low-
pressure limiter are defined for safety p urposes, not for emergency operating conditions.
Upper setpoint (bar) (1)
-
0.5 … 7
Dif ferential setpoint (3)
0.5 … 5
Lowest setpoint (bar)
-0.9
Factory setting (bar)
3.5 - 4.5
Leakage reset pressure (bar)
24
Connection port
Solder 6 mm
Table 18
1. Upper setpoint range spindle
2. Lower setpoint
3. Dif ferential spindle = variable
Figure 21
▪
PS1 pressure switches come with individually adjustable differentials.
▪
Use a f lat screwdriver or a ¼" refrigeration (square) wrench to adjust setpoints.
▪
Adjust upper setpoint (1) using the range spindle (1).
▪
Adjust lower setpoint (2) by turning the differential spindle (3).
2.15.3 Fan operation in rescue mode
Depending on ambient conditions it might be sufficient to have one f an running during emergency
operation. Fan 1 (motor M3, fuse
F6
) is the leading fan in rescue mode.
If low ambient conditions require only one fan running, the second fan (motor M4, fuse
F7
) must be
switched off (by switching off f use
F7
). Switching off the leading f an M3 with f use
F6
will also
deactivate the second fan M4.
Summary of Contents for Copeland OLE-49
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