Polarity Selection
Output polarity can be changed by removing the unit’s left side cover and changing
the polarity selector board’s location. The board is symmetrical by design. Polarity is
not affected by orientation. When the unit’s NIM bin power is turned on, the front
panel POLARITY preview LEDs will indicate the current polarity selection. Canberra
recommends that the polarity selection be verified before turning on the unit’s NIM
bin power. Factory set to POSitive.
J4, Brightness Control
Jumper J4 sets the display brightness to HIgh or LOw (factory set to LOw). In the HI
position, the display is at its brightest, but the unit will draw significantly more cur-
rent. See the Power Requirements specification in Appendix A for details.
Inhibit Control
The Inhibit Function, which is independent of the Voltage Control’s setting, allows the
output voltage to be conditionally turned off or latched off by grounding or by apply -
ing a logic 0 (
≤
0.7 V) to the rear panel INHIBIT connector. The front panel INHIBIT
STATUS indicator lights when the output has been inhibited.
Jumper J5
The INHIBIT input is compatible with all Canberra preamps for either position of
Jumper plug J5; it isn’t necessary to set jumper plug J5 to match the HV INHIBIT
logic high level of the associated Canberra preamp.
Jumper J5 selects the pull up/clamp voltage level of the INHIBIT input for compatibil-
ity with INHIBIT signals from instruments made by other manufacturers. With J5 in
position 5 (factory setting), the pull up/clamp level is set to +5 volts. With J5 set to po-
sition 12 the pull up/clamp level is +12 volts. Please consult the manual provided with
your instrument for its requirements.
Jumper J6
Jumper J6 selects the Latched Inhibit Mode or the Conditional Inhibit Mode.
In the Latched Mode (jumper position A; factory setting), pressing the front panel
RESET button when a logic 1 or open circuit is present at the INHIBIT connector will
restore the output voltage. In the Conditional Mode (jumper position B), an INHIBIT
input of
≥
2 V or an open circuit enables the output.
6
Operating Instructions
