Emerson Process Management MSL600 manual Fault mode relay RL1 and RL2 parameters P560 to P570

Installation, Operation & Maintenance Manual

IP262/Z0, Rev. AB

February 2012 MSL600

7.6.1.2Fault mode (relay RL1 and RL2 parameters P560 to P570)

There are several fault conditions which can be assigned to a relay. Fault conditions may be selected to be signalled by relay, current, both relay and current, or not at all.

Messages describing active faults are automatically written to the lower HMI display.

When a fault condition occurs, a relay configured in fault mode will de-energise. Fault conditions are listed below:

￿Memory Fault - P560

A memory fault occurs if system memory has been corrupted. On occasion the control unit may indicate a memory fault when first powered up. This is normal because the unit is automatically loading default settings in to the memory. After the first power up this fault message should not occur again. All control units are first powered up prior to leaving the factory. If the memory fault message appears after the unit has been switched on and off at least once then consult the factory.

￿CU Temp Fault - P561

A fault is indicated if the temperature within the control unit exceeds pre-set limits.

￿Xdr Temp Fault - P563

A fault is indicated if the temperature within the transducer unit exceeds pre-set limits.

7.6.1.3Set point mode (relay RL1 and RL2)

The relays can be operated in set point mode. See also section 7.6.2.

For example:

If it is required to turn a pump on using relay 1 when the sludge blanket reaches a depth of 3.5m (11.5 ft), then 3.5 (11.5) is programmed in to P411 (RL1 on point).

Note:

It is advisable that the "On" and "Off" points are always set to different values, nominally 50mm (2 in/0.16ft) apart.

7.6.1.4De-sludge mode (relay RL1 and RL2)

The relay can be programmed to operate in de-sludge mode. The de-sludge parameters are described in section 7.3 of the manual.

7.6.1.5On mode (relay RL1 and RL2)

The relays can be switched permanently on if required.

7.6.1.6Off mode (relay RL1 and RL2)

The relays can be switched permanently off if required.

7.6.1.7None mode (relay RL1 and RL2)

If the relay mode is set to "None" then the relay remains in its last valid state i.e. if the relay is "On" and the mode is changed to "None", the relay remains "On".

7.6.1.8Sludge Level Limits mode (relay RL1 and RL2)

If the relay mode is set to Slg Lev Limits, the relay is energised above the Relay On point. It is also energised below the Relay Off point. However, the relay is de-energised in between the "On" and "Off" points.

7.6.1.9Temperature Over Limits mode (relay RL1 and RL2)

If the relay mode is set to Temp OL, the relay is energised above the minimum and maximum control unit operating temperatures. The relay is de-energised while temperatures are within the normal operating range.

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