Troubleshooting guide

MAGNUM VERSION 8 MANUAL REVISION 3.1
100
liquid level is stable and in the control range then the valve is being controlled properly. To accomplish this control
of the CLLC valve is based upon the level of the condenser liquid level.
The value of set point #216 contains the target and the ‘Time(sec)’ field provides a plus and minus dead band. For
example if the value is 60.0 and the ‘Time(sec)’ field is 3 then the control zone will be between 57.0 and 63.0. An
additional control range is developed by adding/subtracting the ‘Time(sec)’ field to the original zone.
Zone
69°
66°
63°
Target 60°
57°
54°
51°
Condenser liquid level positioning: 7.78.10.
 If the condenser liquid level is in ZONE 1, no change to the valve position will be made.
 If the condenser liquid level is above the target and in ZONES 2, 3, or 4, the rate of change of the condenser
liquid level will be checked. If the rate of change is less than the negative value of set point #216, this indicates
that the condenser liquid level is decreasing a rate fast enough make no change to the valve positioning. The
valve state will indicate that the valve is holding.
 If the condenser liquid level is above the target and in ZONES 2, 3, or 4, the rate of change of the condenser
liquid level will be checked. If the rate of change is greater than the negative value of set point #216, this
indicates that the condenser liquid level is NOT decreasing a rate fast enough; therefore, the valve position
must be increased, opened. The valve state will indicate that the valve is opening.
 If the condenser liquid level is below the target and in ZONES 2, 3, or 4, the rate of change of the condenser
liquid level will be checked. If the rate of change is greater than the value of set point #216, this indicates that
the condenser liquid level is increasing a rate fast enough make no change to the valve positioning. The valve
state will indicate that the valve is holding.
 If the condenser liquid level is below the target and in ZONES 2, 3, or 4, the rate of change of the condenser
liquid level will be checked. If the rate of change is not greater than the value of set point #216, this indicates
that the condenser liquid level is NOT increasing a rate fast enough; therefore, the valve position must be
decreased, closed. The valve state will indicate that the valve is closing.
Condenser Liquid Level Adjustment 7.78.11.
 If the valve type is a Relay Output, the pulse time and pulse delay will be the same for all zones.
 If the valve type is an Analog Output, the amount of valve adjustment will be the difference from the
Condenser Liquid Level Target (Setpoint #216). The adjustment will be limited to the setting of the ‘Window to
Extend Safety Time’ of Setpoint #216. This is true for all zones.
Condenser Liquid Level Time Delay 7.78.12.
The delay between determining if an adjustment to the valve is required varies based upon the zone. Zone 1 is the
‘Time(sec)’ of Setpoint #217. Zone 2 is this time divided by 2, Zone 3 is divided by 3, and Zone 4 is divided by 4. Thus
the farther from the Condenser Liquid Level Target the quicker the system checks for valve positioning.
Valve Hold
Valve Closing
Valve Opening
Reduce Delay/3 Valve State =
Reduce Delay/2
Check slope of liquid level if
less than Setpoint open valve
Check slope of liquid level if
greater than Setpoint close valve
Reduce Delay/2
Reduce Delay/3 Valve State =
Valve State =
3
1
1
2
3
4
2
4
Reduce Delay/4
Reduce Delay/4