SECTION TWO
INSTALLATION
HEALTH AND SAFETY NOTE
Important
British Government Health and Safety at Work Act, 1974
In view of the above Act it is necessary to draw your attention to the following.
On adaptors/flanges fitted between the a.c. generator and engine the openings must be guarded. Where integral
guards are not provided an external protection cover must be fitted.
All a.c. generators are designed with screen protected and drip proof enclosures and as such are not suitable for
mounting outdoors unless adequately protected by the use of canopies.
VENTILATION
When installed in a room without special ventilation arrangements it must be ensured that the ambient temperature of
the normal operating conditions does not exceed the maximum value for which the machines are designed. (Normally a
maximum of 40ºC). Heat dissipation and cooling air requirements are available on request.
INITIAL CHECKS
If it is necessary to store the machine for long periods, the storage accommodation should be clean, dry and well
ventilated. We would recommend the use of anti-condensation heaters to ensure that winding insulation is kept in a
good condition where machines are stationary for long periods, i.e. standby plant. Before installation of an a.c.
generator which has been kept in storage the insulation resistance of the windings should be checked using a megger
or similar instrument. It is essential that the automatic voltage regulator (A.V.R.) is completely isolated before testing,
otherwise damage to the electronic components may be sustained. If radio interference suppression capacitors have
been fitted in the terminal box these should also be disconnected. If the tests show that the insulation resistance is
below 0.5 of a megohm, the machine should be dried out and the test made again. With a completely dry machine the
resistance value should be at least 2 megohms. The machine windings can be dried out by applying warm air from a
fan heater or similar apparatus into the machine openings. Alternatively, the main stator windings may be short
circuited, and the generating set run with the exciter stator supplied from a d.c. source. A 12 volt 0.5 amo d.c. supply
should be connected to the exciter stator leads, marked X and XX
Normally no longer than half an hour will be required for drying out windings in this manner. After this period of
time the insulation level should be checked and the drying out Procedure repeated if necessary.
VOLTAGE ADJUSTMENT
As the machines are offered for a broad operating voltage range it may be necessary to adjust the factory set voltage to
meet individual requirements and this should be carried out as follows.-
1.
Remove A.V.R. box lid (SC type) or terminal box lid (PC type).
2.
Adjust VOLTAGE RANGE control to required voltage.
3.
Adjust STABILITY CONTROL (only if necessary) until stable operation is obtained 'ON and 'OFF' load.
(Turning control clockwise increases A.V.R. 'gain').
If a hand trimmer has been supplied for remote voltage control, fine adjustment to the nominal voltage level set by the
RANGE control can be made. (See page 31 for details).
UNDER FREQUENCY PROTECTION ADJUSTMENT
This is set for 50 Hz or 60 Hz operation by means of a "JUMPER" lead on the A.V.R.
3