Berkeley Nucleonics Corporation
2955 Kerner Blvd., San Rafael, CA 94901 ° Tel (415) 453 9955 ° Fax (415) 453 9956 ° www.berkeleynucleonics.com
LED
FUNCTION
LED1
Enable Indicator. If the driver is enabled, the LED will be
illuminated. If it is disabled, the LED will be off.
LED2
+5 VDC Monitor. If the +5 VDC on-board regulator is
functioning correctly, this LED will be illuminated.
LED3
+15 VDC Monitor. If the +15 VDC on-board regulator is
functioning correctly, this LED will be illuminated.
LED4
-15 VDC Monitor. If the –15 VDC on-board regulator is
functioning correctly, this LED will be illuminated.
LED5
+24 VDC Monitor. Ind24 VDC is applied to the
driver.
D27
Interlock Fault – indicates the interlock reed switch is
open.
D28
Over Temperature Fault – indicates maximum heat sink
temperature has been exceeded.
D29
Under Voltage Fault – indicates input voltage is below 18
Volts.
5.9 +24VDC Input
The +24 VDC input provides the power for the output current. This voltage may be in
the range of +20 V to +28 V. It may be unregulated if it does not vary below 20 V or
above 28 V.
At 125 A output, the driver dissipates ~75 W when enabled but not pulsing.
Efficiency is therefore the ratio of output power to the input power or η = output
power / (idle power + output power). The idle power consumption varies non-linearly
with output current and can be approximated by the formula P=I
2
x 0.005 where I is
the output current. For example, at 75 A output current, the idle power consumption
is 75
2
x 0.005 = 28 W.
The +24 VDC support power should be sized for the average output power (Power x
Duty Cycle) plus the idle power consumption as defined above, and an additional
20% for pulse switching losses.
5.10 Power-Up Procedures
1. The unit should be powered up using the following procedures:
2. Before connecting the input pulse generator to the PCO-6131 pulser, set up
the pulse generator output to deliver a CMOS level pulse with a repetition rate
and pulse width appropriate for the laser diode being driven. Before connecting
input connector J2 to the driver, turn off or disable the output of the pulse
generator.
3. Connect the input connector J2 prior to ap24 VDC support power.
4. Connect the +24 VDC support power to connectors E1, E2, E3 and E4.