2005

SECTION 4

MAINTENANCE

4-1.

GENERAL

Under normal conditions, no special maintenance of the Model

2005 is required. If servicing is necessary, the information in

this section should be read thoroughly before starting repair or

calibration.

4—2.

ADJUSTMENT AND CALIBRATION

Make the following adjustments whenever a component is replaced

or periodic recalibration is scheduled:

a.

Preliminary Meter Adjustment:

(i)

Mechanically zero the meter using the adjustment screw

on the front panel.

NOTE

Before completing any meter adjustment, lightly

tap the meter face. This will overcome any pivot

friction and insure proper calibration.

(2)

Set the CURRENT LIMIT ADJ control fully clockwise.

(3)

Connect a 40—ohm, 10—watt resistor, in series with

a standard ammeter, across the output of the supply.

(4)

Set the AC switch to ON and adjust the output voltage

controls for a convenient reading, approximately ampere on a standard

ammeter.

(5)

Set the meter switch to MA.

(6)

Adjust potentiometer R42 (on the board behind the meter)

until the panel meter reading agrees with that of the standard ammeter.

b.

Zero Voltage Calibration:

(1)

Connect a high precision voltmeter across the output

of the supply.

(2)

Set the RANGE switch to the 0-10V position and the output

voltage controls for 0.000 volt output.

(3)

Set the AC switch to ON and observe the voltmeter.

(4)

If the voltmeter does not indicate 0.000 volt ±1 MV,

adjust CALIBRATE potentiometer R39 (on the rear panel) for this reading.

If the adjustment is beyond the range of R39, proceed as follows:

645

4—1