General Operation - Lowara GEMK Serie Instrucciones Para La Instalación Y El Uso

5.1.4 Checks on other system components
Check the correct position and assembly of all the system components, such as the silencer and exhaust gas pipes, the
combustion and cooling air inlet system, the cooling air evacuation system, etc.
Make sure that the air filters are clean and that the intakes and exhausts are free from obstructions.
5.1.5 Starting batteries
Preparing the battery
The starting batteries supplied with the set are usually low maintenance type and pre-charged.
The battery is considered exhausted when the voltage is lower than 12.4V, but an accurate test can be done using a
densimeter.
In the case of long periods of storage (of more than 2 months), read with care the use and maintenance
ATTENTION
manuals provided with the diesel engine and batteries. Follow the instructions in these manuals.
Recharging the battery
If you need to recharge the batteries, connect the diesel pump electric panel power supply approximately 24 hours before
starting the diesel engine, so the backup battery chargers situated inside the panel have the time to give an initial charge to the
batteries.
Set the key-operated selector switch to the "0" position to prevent any accidental start-ups.
If the battery charge is lower than 10V, the backup battery charger in the panel cannot be used and the battery must be
disconnected for reconditioning or replacement.
Positioning
The batteries must be mounted on supports, located in an easily accessible position with the minimum possibility of
contamination from humidity, water or vibrations.
The starting batteries must be positioned as close as possible to the starting motor of the diesel engine,
ATTENTION
observing all the requirements to minimize the drop in voltage between the battery and the terminal of
the starting motor.
5.1.6 Circuits and electrical panels
If the set has been out of operation for a long time, especially in a humid environment, you should check the ground isolation of
the electric panel and make sure the auxiliary circuits are properly supplied with power.
(Refer to the panel wiring diagram)
5.2

General operation

Refer to the chapter on use and maintenance of the electric panel for information on the operating logic of the diesel pump
(operation in DISABLED/MANUAL/AUTOMATIC/EMERGENCY mode).
The pumps may only be stopped manually by operating a STOP button, with the exception of the version for fire-hydrant
networks, where the pump shuts off automatically after the pressure has been restored for the length of time specified by the
regulations locally in force.
The automatic starting of the pumps is determined based on the pressure switch settings. There are two pressure switches for
each service pump (or one in the case of the electric jockey pump), both having the same settings and being connected in such
a way as to start the pump when either one of them is triggered.
The differential pressure (the difference between the start-up and shutdown pressure) is the same for both pumps and is in the
region of 0.6 to 1 bar (value of setting can be changed in function of performance pump curve).
As provided by the firefighting standards, the first pump starts up automatically when the pressure in the main piping drops to a
value no lower than 0.8 Pmax (Pmax pressure with delivery shut off). The second pump starts when the pressure drops to a
value no lower than 0.6 Pmax The diaphragm tank and/or jockey pump, if present, serve to compensate for small system losses.
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