Wayne Kerr AP10030, Руководство пользователя и обслуживания

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Wayne Kerr AP 1kW Power Supplies • Issue 2 17
Replace the protective terminal cover (it is held on by 2 x M3 screws) over the busbars
and the barrier strip before enabling the output. load leads may pass through the gap in
the bottom of the cover. N.B. The output is inhibited when this cover is removed.
Earthing the Load
Either the +ve or -ve busbar can be earthed to produce negative or positive voltages
relative to ground. A M5 threaded insert on the back panel (which is connected to ground
via the units mains lead) is provided to give a common earth point thus minimising earth
loop problems.
If neither terminal is connected to earth, the output can be floated up to a maximum of
120V d.c. (including output volts), away from earth potential. When a second earth is
added to the system a 200V float is permissable.
6.3 Protective Circuits
Circuits within the power supply will limit the output power or inhibit the system
operation (i.e. reduce output to zero) under certain conditions. LED enunciators on the
front panel indicate when one of the protection circuits is activated.
6.3.1 Overrange (UNREG)
An ‘over-range’ condition is indicated by the ‘UNREG’ (output unregulated) LED being
illuminated and no other LEDs in the status area being lit. The green output enable LED
will be illuminated.
The over-range condition occurs when the output power demanded from the supply
exceeds 1000W. The output does not shut down but will be limited with a constant
power output of just over 1000W. This condition will occur if the load connected is such
that neither the set voltage nor current limit setting can be reached without the load
taking more than 1000W.
Over-range may also occur if a current limit setting of greater than the maximum
specified output current is demanded.
6.3.2 Overvoltage Limit (OVL)
This circuit will operate whenever the output voltage exceeds that set by the overvoltage
adjust or when the output voltage exceeds a factory set overvoltage limit (approximately
10% greater than maximum output voltage).
The overvoltage trip is indicated by the ‘OVL’ LED being illuminated. The power supply
output will shut down, the meters will read approximately zero and no other indicators
(including the green output LED) will be illuminated.
Adjusting Overvoltage Trip
The trip point is adjustable by means of the multi-turn, screwdriver adjustable, ‘OVL
adjust’ on the front panel.
The trip setting can be seen by pressing the ‘display OVL’ button on the front panel. This
displays the overvoltage setting on the voltmeter. The setting can be viewed at any time
whether the power supply output is enabled or not. It is recommended that the trip point