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9. Verification Procedure
The following procedure can be used to determine if the 3M
™
Charge Analyzer 711 is operating within the stated
specifications:
Equipment required
• DC ± 5,000V (
≤
± 1% tolerance) adjustable high voltage power supply
• Four lead wires (banana plug style)
• Digital Multimeter (Voltmeter scale),
≤
± 0.1% tolerance
Charge Analyzer 711 Internal Sensor
1. Mount the cup electrode (a) to the top of the analyzer and perform the zeroing function described in Section
5. Voltmeter Operation / Setup.
Important Note
•
Do not discharge to the sensor element.
2. Connect a lead wire between the ground jack of the unit and the low/return side of the DC high voltage
power supply.
3. Connect a lead wire between the DC power supply output connection and the banana jack of the cup
electrode (a).
4. Connect remaining two wires between the digital voltmeter (± voltage inputs) and the red/black banana jacks
(analog output) at the rear of the analyzer. (Select meter scale ± 2vdc)
5. Select the proper range on the unit, apply DC high voltage power supply to each full range,
(25 VDC,
100VDC, 500VDC, 1,000VDC, and 5,000VDC).
Verify that the display indicates within ± 2.5% of full
range. See verification check list form on next page.
Note: Also verify during step 5 that the analog output is within tolerance. Input to output ratio for each
voltage range is as follows:
711 Voltage Range Setting
Ratio Input to Analog Output
Multiply analog output voltage by
the appropriate value below to
obtain 711 input value.
Decimal Value
Multiply input voltage to the 711
by the appropriate factor below to
obtain analog output value.
25Vdc
12.5 to 1
0.08
100Vdc
50 to 1
0.02
500Vdc
500 to 1
0.002
1,000Vdc
500 to 1
0.002
5,000Vdc
2500 to 1
0.0004
6. Repeat Step 5 for Negative voltages.
