HP 6269B Operator’s, Organizational, Direct Support And General Support Maintenance Manua L page 31

TM 11-6625-2958-14&P
tions of output voltage and current on the dc volt-
meter and ammeter. Both meter movements can
withstand an overload of many times the maximum
rated output without damage.
4-66 The ammeter together with its series resistors
(R101, R105) is connected across current sampling
resistor A4R123. As mentioned previously, the
voltage drop across the current sampling resistor
varies in proportion to the output current.
ometer R101 is adjusted for full scale deflection
(calibration) of the ammeter.
4-67 The voltmeter, in series with R103 and R104
and shunted by R102 and R106, is connected direct-
ly across the output terminals of the supply. Poten-
tiometer R106 permits calibration of the voltmeter.
4-68 ADDITIONAL PROTECTION FEATURES
4-69 The supply contains several "special pur-
pose" components which protect the supply in the
event of unusual circumstances. One of these
components is diode A4CR106. Connected across
the output terminals of the supply, it prevents in-
ternal damage from reverse voltages that might be
applied across the supply. This could occur, fo
example, during Auto-Series operation if one sup-
ply was turned on before the other.
Potenti-
4-70 Resistors R108 and R109 limit the output of
the supply if the connections between both output
buses and the sensing terminals (+S and -S) are in-
advertently removed.
4-71 Diode A4CR105, previously mentioned in the
series regulator description, protects the regula-
ting transistor from the effects of reverse voltages.
4-8
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