Global Specialties 1505 - Manual (Page 7)

SECTION - 4
OPERATING INSTRUCTIONS
a) 1505 as Isolated Variable AC Supply.
Set output voltage to ‘0’ volt by turning the 'Set Voltage' knob to
minimum position. Press push button switch marked 'V'
Keep the output voltage selector switch to the desired range
(0 -130V or 0 -260V). Isolated variable voltage will be available at the
respective output socket only.
Switch "POWER"ON. Adjust the voltage control knob till the
desired voltage is indicated on the 3-digit DPM.Connect the load
at the output. Press push switch marked 'A'.The DPM will now read
the load current. The total load current should not exceed the
maximum rating indicated for each range.
b) 1505 as Line Leakage Tester.
Set output voltage to ‘0’ volt by turning the knob to minimum
position. Press push switch marked ‘V’. switch "POWER" ON.
Adjust the voltage control till the desired voltage at which leakage
current is to be measured is available at the output socket.
Now press push switch marked ‘mA’. Connect unit under test (U.
U. T) to output socket. Connect the leakage test probe at the socket
marked 'Leakage Test'. Connect the other end of the leakage test
probe to the chassis of the unit under test. Depending on the
leakage,the DPM will read the leakage current.
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SECTION - 6
CALIBRATION PROCEDURE FOR MODEL 1505
1) Keep the Voltage knob to minimum position(ccw). Press push
switch marked ' V '
2) Switch on the power.
3) Set reference voltage of DPM(pin no. 36 of U1-7107) to 1.00Volt by
adjusting the preset VR1 on DPM pcb.
4) Set voltage at pin no. 6 of IC3 (CA3160) to zero Volts with the help
of preset PR4 on switch pcb.
VOLTAGE CALIBRATION
5) Set desired output voltage by turning Voltage knob in clockwise
direction.Connect external AC voltmeter at the output.
6) Adjust preset PR2 on switch pcb so that DPM reading matches
with external AC Voltmeter.
CURRENT CALIBRATION
7) Press push switch marked ' A ' . Connect load at the output with
AC current meter in series with the load.The DPM will now read
the load current.(The load current should not exceed 2 Amps/
4Amps for Range A/B respectively.)
8) Adjust preset PR3 on switch pcb so that the DPM reading matches
with external AC current meter
LEAKAGE CURRENT CALIBRATION
9) Set output voltage to zero volt s by turning the Voltage knob to
minimum position.
10) Press push switch marked ' V '
11) Switch on the power.Adjust output voltage to 130VAC.
12) Press push switch marked ' mA '. now DPM will read leakage
current.
13) Connect 25 Kohm (aprox.1W) resistor across banana socket,
marked 'LEAKAGE TEST', & live point of output socket. Adjust
preset PR1 on switch pcb so that DPM reading is 5.00mA
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