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Magnum System Alarms
Configuration Alarms
These alarms indicate a problem with the configuration file in the system. The system is not operational and a new configuration must be transmitted to the unit
through MCS-Connect.
• INVALID CONFIG - Checksums are incorrect.
• INVALID CFG VER - The version number of the configuration is invalid.
• INVALID CFG TYPE – The configuration type does not match the software type.
MCS Local Network Alarms
These alarms indicate problems with the MCS local network:
• LOST SI COMM #_ / LOST RO COMM #_ - Generated when communications to a Sensor Input or Relay Output board
is lost. The number of the board will be displayed with the alarm. The system can be accessed but will be in a NO RUN- I/O LOST state.
• MCS-STAT OFFLINE - The Magnum has lost communications to the MCS-STAT.
• LOST IO SHUTDOWN - Generated when Magnum is running and there are no communications to one or more of the
I/O boards. The system can be accessed but will be in a NO RUN- I/O LOST state.
• LOST I/O RESTART - Generated when the Magnum does an automatic reset once I/O communications are restored.
Key Sensors Alarms
These alarms indicate a problem with a key sensor, it is either shorted or open. The alarm will contain ALARM followed by the
10-character name of the sensor. The following sensors related to the entire system are tested:
• Leaving temperature: If failed, then Lock Out the system.
• Returning temperature: If failed, then alarm only no Lock Out.
• Ambient temperature: If failed, then alarm only no Lock Out.
The following compressor sensors are tested. If they fail, then that compressor only is locked out:
• Suction pressure and temperature
• Discharge pressure and temperature
• Oil pressure and temperature
• Motor temperature (if an analog input)
Emergency Stop Alarm
• EMERGENCY STOP - Generated when the emergency stop switch has been turned on. The system can be accessed but is in a Lock Out state.
Setpoint Safety Alarms
The Magnum algorithm incorporates a number of safety checks, based on setpoints, preventing unsafe conditions that could
potentially cause damage to the system. When a safety trips, the circuit will be in a SAFETY TRIPPED state. The circuit will remain
in this state for the time in the ‘Safety Down Time (min)’ cell and then move to the CMP ANTICYCLE or CMP IS OFF state where
the compressor will be allowed to run again if required. If the same safety trip occurs again within the time in the‘Lockout Delay Hrs’ cell since the first trip, the
circuit will be set to CMP LOCKED OUT state, which requires a manual reset to restart the compressor. If the lockout delay time is set to zero, the Magnum will
generate a lockout condition the first time that the safety occurs.
Sensor Inputs Used With Magnum
• Suction Pressure (Analog) Discharge
• Pressure (Analog) Discharge
• Temperature (Analog) Motor
• Temperature (Digital) Motor Amps
• (Analog)
• Motor Fault (Digital)
• Suction Temp (Analog Only) Oil Sump
• Level (Digital Only)
Setpoint Safeties
For a safety trip to occur, both the Sensor Input and the associated setpoint must be active. If a safety trips, the alarm name will
consist of the setpoint name plus additional identification such as point number, compressor number, or 30 second history leading
up to the trip if applicable.
NOTE:
Most safeties are checked only if the compressor is running, however if the safety is always checked it will be noted.
The following is a list of safeties that are incorporated in the standard algorithm control. These safeties are checked every second. For a system with multiple
circuits, each one is tested individually. If a safety trip occurs, only that respective compressor will be affected, the others will continue to function normally.
Phase Loss Protection
Phase loss, as indicated by the phase loss monitor, will result in the entire system being Locked Off and a phase loss alarm will be generated. If setpoint #166
is inactive, the Magnum will wait for 2 seconds before the Lock Out occurs. The alarm will be PHASE LOSS and no restart will be attempted. If setpoint #166 is
active, the name of the setpoint will be in the message. Refer to section 13 setpoint #166.