Page 44 - Uninterruptible Power Supplies

Standby Power Generating Sets
42 Chapter One

■ Low lubricating oil pressure
■ High cooling water outlet temperature or, for air-cooled sets, high
cylinder head temperature
■ Operation of the engine overspeed trip
■ Failure of the governor speed sensing signal magnetic pick-up
■ Operation of the engine room fire detection system
■ Tripping of the standby supply circuit breaker on fault or overload
■ Failure to start after the appropriate cranking sequence

The first two parameters, low oil pressure and high coolant temper-
ature may be monitored in two stages, the first stage being a warning,
the second stage being a shut down. The warning stage is useful only if
skilled personnel are available who can diagnose the condition and
take remedial action.

Remote Control and Monitoring
Manufacturers of engines and generating sets are able to offer compre-
hensive control and monitoring systems operating from a central loca-
tion. For continuously running plant such an arrangement can be very
useful but for standby generating plant the advantages are obviously
fewer.

Remote Control Systems and Test Runs
Depending on the degree of technical knowledge and ability that is
available locally, it well may be worth considering the benefits of a data
link to a remote base. The remote base can be staffed by the user orga-
nization, the plant manufacturer, or a specialist organization.
At locations where competent technical staff are available, the local
staff can arrange test runs at regular intervals and in doing so they
benefit from becoming familiar with the installation. A remote control
system would be of little benefit. At locations where there is no on-site
technical staff, a remote control system can initiate and complete reg-
ular test runs without the need for any local personnel becoming
involved (except for giving permission for the test run). The system
would involve monitoring the status of the installation to ensure that
the set is ready to start; has adequate fuel, lubricating oil, and coolant;
and that the electrical distribution system is in its normal healthy con-
dition.
At locations which do not have technical staff and are isolated or dif-
ficult of access, a remote control facility could be useful. The staff
responsible for operation and maintenance will be remote from the

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