Maintenance And Calibration; Variable 0-20Vdc Regulator Calibration; Variable 0-40Vdc Regulator Calibration; Digital Meter Calibration On Model Xp-750 - Elenco Electronics XP-650 Instruction Manual

Maintenance and Calibration

The Elenco Models XP-650 and XP-750 have been designed and manufactured to require no routine main-
tenance. The circuits are protected by design from external shorts or overloads. The following information
is provided in the event the supply requires service or re-calibration.

Variable 0-20VDC Regulator Calibration

1) Connect an accurate digital meter to the output terminals.
2) Set the voltage control to the maximum position and switch to 0-20V.
3) Adjust the variable resistor VR1 for 20.0V.

Variable 0-40VDC Regulator Calibration

1) Connect an accurate digital meter to the output terminals.
2) Set the voltage pot to maximum position and voltage switch to 0-40V position.
3) Adjust the variable resistor VR2 for 40.0V.
Digital Meter Calibration for Model XP-750
1) Note the small pot (R2) on the top of each meter's PC board. This is the GAIN pot which controls the
accuracy of the meter.
2) To set the accuracy of the meter you need another very accurate digital meter. Connect this meter to
measure the voltage on the output terminals. Set the voltage switch to 0-40V position and set the out-
put to 30VDC. Adjust the voltmeter GAIN pot for 30.0 volts on the XP-750 meter.
3) To set the accuracy of the ammeter connect a suitable load to the output and connect the accurate dig-
ital meter to measure the current on the load. Set the voltage switch to 0-20V and set the output cur-
rent to 2.0 amps. Adjust the ammeter GAIN pot for 2.00 amps on the XP-750 ammeter.
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