Maximum Crowbar Trip Voltage - HP 6269B Operator’s, Organizational, Direct Support And General Support Maintenance Manua L

TM 11-6625-2958-14&P
be set much closer to the operating
output voltage of the supply.

5-109 MAXIMUM CROWBAR TRIP VOLTAGE

5-110 To adjust the maximum voltage at which the
crowbar trips, proceed as follows:
a. Rotate A5R125 (OVERVOLTAGE ADJUST)
and CURRENT controls fully clockwise.
b. Disconnect either end of R72 (TP70 or
TP71; see Figure 7-10).
c. Connect decade resistance box in place
of R95 (mounted on standoffs on main circuit
board).
d. Turn on supply and adjust VOLTAGE con-
trols for output voltage shown below:
Model
6259B
6260B
Value
12Vdc
12Vdc
5-22
Model
6261B
6268B
6269B
e. Adjust decade resistance box until crow-
bar trips (amber OVERVOLTAGE lamp lights up).
f. Replace decade resistance with appro-
priate value resistor in R95 position and reconnect
resistor R72. Maximum crowbar trip voltage is
now set at voltage given in Step (d).
5-111 CROWBAR DISABLEMENT
5-112 To disable the crowbar completely, discon-
nect either end of R98 (TP97 or TP98). This resis-
tor is mounted on the main circuit board (see Fig-
ure 7-10).
Value
23Vdc
45Vdc
45Vdc