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1TTS900001M0902
7. Auxiliary circuits According to the diagram, check the
functionality and the operation logic
sequences of the auxiliary circuits
Before performing this
inspection, check the
calibration of each relay of the
switchboard
8. Anticondensate heater • Feedthecircuit
• Adjustthethermostattothe
higher temperature allowed
• Checkthattheheater
temperature raises
• Adjustthethermostatsothat
the temperature inside the
switchboard is always higher than
the outside ambient temperature
(approximately 35° C)
• In case of particular apparatus configuration, it is possible that the previous inspections must be
integrated with others suggested by the technician responsible for the apparatus.
• Check that the current transformer secondary winding is connected to the related protective and/or
measuring amperometric circuit, then remove any possible short-circuit connections.
• In case the voltage transformer secondary winding must be connected to switchboard external equipment,
check for the following conditions, to avoid overloads or short-circuits in the voltage transformers:
- Check that the total comsumption of the equipment is not superior to the transformer capacities.
- Check for incorrect connections (also provisional) in the measuring circuit or connections not in
accordance with the switchboard connection and other units (supply switchboard, subswitchboards,
control or operating desks, etc.).
- Check that only one phase of the voltage transformer secondary winding is earthed.
• At the end of the preliminary test, carry out the following operations:
- Open and isolate all the circuit breakers
- Remove any testing connections
Close all doors of the circuit breakers and measuring cells
Check for internal metal segregations (according to the design constructive shape) of the external
closing panels
- Check that the different mechanical and electrical interlocks (possibly deactivated to carry out start
test with switchboard not powered) have been restored.
• Feed the control circuit
• Close the circuit breakers (according to system requirements), and ensure that any related function
operates regularly
• Check the correct operation of the auxiliary instruments.
Respect the general safety rules
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