Troubleshooting guide

MAGNUM VERSION 8 MANUAL REVISION 3.1
152
# Name Description
106 LEAD PUMP Indicates which pump is the lead. If zero, then rotation of the pumps will occur whenever the
lead pump is turned off. If no rotation has occurred during the current day, a forced
rotation will occur at midnight, ensuring at least one rotation per day. If value is non-zero,
then rotation of the pumps is inactive and the value will specify the lead pump. This
Setpoint can be changed in a live unit and the appropriate action will be taken
immediately.
107 EcoDelayMech Seconds to delay after the economizer is fully loaded, valve opened to its maximum, and all
associated fans are on before the mechanical cooling is enabled. If inactive, then the
value of Setpoint #125 “Eco StageDly” will be used for this delay.
‘Time (sec)’ field: This value is used as a multiplier in the calculation that determines when it
is too cold to use economizer cooling. If the control temperature drops below Setpoint
#1”CTL TARGET” minus (‘Time (sec)’ field of this Setpoint multiplied by the value of
Setpoint #3 “CTL ZONE -“) then shut off all economizer cooling. If the value in this ‘Time
(sec)’ field is zero, a hardcoded 3 will be used instead.
108 PUMP DELAY Time in seconds to keep the chilled water pump running after the last compressor has been
turned off to ensure the chiller barrel does not freeze.
109 HiRefLevel This Setpoint has two functions.
If active, the Magnum checks for high refrigeration level. If the refrigeration level sensor is
greater than this value for the specified period of time, a safety trip occurs.
If active, system has EXV valve control based on refrigerant level, and the refrigerant level is
greater than this value, then the EXV valve adjustment will be set to the value in Setpoint
#13 “EXV COURSE” * ( –3).
Refers to ‘Refrig Level’ column in the Circuit SI screen
110 RefLvlExvAdj
(EXV Control:
Refrigerant Level)
If Setpoint #84 “LO DiscSPRHT” is active and it has reached one third of its safety time, then
Setpoint #9 “REF LVL TRG” will be set to the value of this Setpoint. The purpose is to
decrease the EXV valve opening to avoid a low discharge superheat safety trip. This
change will be updated in the Setpoint status value.
DSprhtExvAdj
(EXV Control:
Discharge or Suction
Superheat)
If Setpoint #84 “LO DiscSPRHT” is active and it has reached one third of its safety time, then
Setpoint #9 “SUPERHT TRGT” will be increased by the value of this Setpoint. The
purpose is to decrease the EXV valve opening to avoid a low discharge superheat safety
trip.
111 FREEZE If active, the Magnum will compare the leaving temperature to this Setpoint. If it is less than
this value for the specified period of time, a safety trip occurs.
112 NO STOP This Setpoint is used to ensure that a compressor is actually off when the controller calls for it
to be off. This Setpoint contains a percentage of the FLA for Setpoints #65-#72. If the
compressor amperage is greater than this percentage of the FLA Setpoint for the
specified period of time, signaling that the compressor is still running, then the entire
system is locked out and a NO STOP alarm is generated. If a Control Power relay is
specified, then it will be turned off when this safety trips.
113 OIL INJ TEMP DIFF This is a temperature differential subtracted from Setpoint #8 to control the oil injection relay.
When discharge temperature is above this differential, then oil injection is turned on. If
inactive then value will be 5.6° F (2.8° C).
114 OIL TEMP DIFF This is a temperature differential used in controlling the oil heater and second liquid line
solenoid. If inactive then value will be set to 5° F.
115
EcoVFDfanDely
If active, and the fluid cooler has a VFD condenser fan, this Setpoint will be the time in
seconds between adjustments to the VFD. If inactive, then the value of Setpoint #124
“EcoVlvAdjDly “will be used for this delay timer.
116
Defrost On Temp
Only used in Turbo Ice Machines. When control temperature falls below this value, then a
defrost cycle begins. When the temperature rises .5° F above this value then the defrost
cycle will be terminated.
117
Defrost On Delay
Only used in Turbo Ice Machines. Time in seconds of pre-defrost delay.
118
Defrost On Cycle
Only used in Turbo Ice Machines. Time in defrost cycle for each circuit.