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TECHNICAL INFORMATION
17
87-900-049-01
(
E
)
INSTALLATION
Inspect the controller for any shipping damage.
•
Models 929-0190 and 929-0191 are factory set for
120 Vac operation
•
Models 929-0290 and 929-0291 are factory set for
220 Vac operation.
WARNING
The MiniVac controller is equipped with a 3-wire power
cord and plug (internationally approved) for user's
safety. Use this power cord and plug in conjunction with
a properly grounded power socket to avoid electrical
shock.
High voltage developed in the controller can cause
severe injury or death. Before servicing the unit,
disconnect the input power cable.
NOTE
The MiniVac controller can be used as a bench unit or
as a rack module, but it must be positioned so that free
air can flow through the holes.
Line Voltage Change Over
If a change in line voltage operation is desired, proceed
as follows:
•
Unplug the power cord from the controller rear
panel socket.
•
On the power entry module (rear panel), check back
door for voltage selector set.
•
Using a small screwdriver, pull out the voltage
selector and fuses.
•
Select the operating voltage, then firmly insert the
voltage selector and fuses in place.
•
Check voltage selector window for correct set and
connect the power cord.
•
For Line Voltage between 200 and 230 Vac set the
voltage selector to 220 Vac; for Line Voltage higher
than 230 Vac set the voltage selector to 240 Vac.
Output Polarity Selection
The output polarity is selected by the high voltage
multiplier card, and is factory set for negative output
voltage polarity. If a change in output polarity is
desired, proceed as follows:
•
Switch off the power and unplug the power cord
from the controller rear panel socket.
•
Undo the 9 screws and then remove the cover.
•
Disconnect the H.V. white wire (1) from the
multiplier board (see the following figure), remove
the board (2) and rotate it 180° horizontally; reinstall
the board into the socket and reconnect the H.V.
white wire.
•
Install the cover and screws.
•
Connect the power cord then switch on the unit and
check on the front panel the output polarity
indication.
Output Polarity Selection
1
2