Figure 5-15 High Voltage ON warning. Wayne Kerr 3260B

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Advanced Operation

The test connections are at a high voltage during this trim. While high voltage is applied, a message, shown in Figure 5-15 below, will be displayed on the screen. To minimize the

risk of electric shock,

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Figure 5-15 High Voltage ON warning

When trimming for manual operation:

1) Ensure that the measurement leads/fixture are connected to the analyzer according to the connection protocol shown in Figure 5-2.

2) Ensure 2-terminal or 4-terminal operation is selected as required for subsequent measurements.

3) Carry out O/C Trim (Pri-Sec) as detailed in section 4.3.2.

When trimming for HANDLER MODE operation:

1) Ensure that the handler/scanner is connected to the analyzer according to the connection protocol shown in Figure 5-3.

2) Either: a) select Handler Calibration from CALIBRATE MODE; or b) select CALIBRATE directly from HANDLER MODE.

3) Select the Insulation Trim soft key.

4) Wait until the analyzer has finished trimming.

Notes:

1) The stored trim values will be applied during 2-terminal insulation tests, even if AC impedance and Rdc trimming correspond to 4-terminal operation.

2) The Insulation Trim soft key is not available when CALIBRATE is selected from

INSULATION MODE.

3) If Insulation Trim is attempted with Kelvin clip leads attached to the analyzer in

HANDLER MODE configuration, the trim will fail because the RED and BROWN leads are shorted by the Kelvin clip.

5.8.3 Operation

The general procedure when using INSULATION MODE is as follows.

1) Select the Menu control key, followed by the INSULATION soft key.

Advanced Operation 5–15

2) Connect the measurement leads to the analyzer according to the connection protocol detailed in section 5.8.1.

3) Select 2- or 4-terminal measurement.

4) Refer to section 5.8.2 and trim the leads/fixture.

5) Select the insulation test required, i.e. Pri–Sec, Pri–GND or Sec–GND, with the appropriate soft key.

6) If the setup parameters are hidden, press Show Setup.

7) Change the setup parameters, i.e. Level, Range and Speed, as necessary for the test.

8) Connect the measurement leads/fixture to the transformer (see section 5.8.1—

Connections).

9) Select the measurement unit to display with the µA MΩ soft key.

10) Press the Trigger control key to initiate a measurement.

5.8.4 Example

This example will take the user through the process of performing all three insulation test types on a transformer. The settings used are examples only and the user may substitute other settings as required. The analyzer should be powered up with two sets of Kelvin clip leads connected to the Primary and Secondary front panel BNC sockets according to the connection protocol shown in Figure 5-2 .

1) Press the front panel Menu control key. The MAIN MENU will be displayed.

2) Press the INSULATION soft key. INSULATION MODE will be displayed.

3) Select either 2- or 4-terminal measurement, as required for subsequent tests, with the 2/4

Term control key. For this example, 4-terminal measurement will be selected.

4) Press the CALIBRATE soft key and perform an O/C Trim (Pri–Sec). If necessary refer to section 4.3.2 for trimming details. When the trim is complete, press the INSULATION soft key to return to INSULATION MODE.

WARNING!

The test connections are at a high voltage during this trim. While high voltage is applied, a message, shown in Figure 5-15 above, will be displayed on the screen. To

minimize the risk of electric shock,

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5) Press the Pri–Sec soft key.

6) Using the µA MΩ soft key, ensure that µA is highlighted.

7) Using the navigation keys, highlight and set each of the following parameters in turn. Use the and navigation keys to highlight a parameter and the and navigation keys to alter the highlighted parameter setting.

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Advanced Operation

Level 500V this can also be set with the data entry keypad.

Range Auto

Speed Med

8) Connect the Primary BROWN BNC connector to one end of the transformer primary winding. Connect the Secondary BROWN BNC connector to one end of the transformer secondary winding. The LEDs above the BROWN BNC connectors should be lit to show that they are the active connections. There should be no other connections to the transformer.

9) Press the Trigger control key to initiate the measurement. Figure 5-15, above, will be displayed while high voltage is applied to the measurement terminals and the measurement result will be displayed.

WARNING!

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S. Although the current is limited to a safe level, there is a risk of electric shock, especially at 200V and 500V test levels. Unless energy is stored in components, e.g. capacitors, connected to the measurement terminals, the voltage at the measurement terminals will be removed within 0.5 seconds of test completion.

10) Press the Pri–GND soft key and, if necessary, re-establish the measurement conditions outlined in steps 6) and 7).

11) Connect the Primary BROWN BNC connector to one end of the transformer primary winding. Connect the GREEN CLIP LEAD to the transformer metal case or screen The

LED above the Primary BROWN BNC connector should be lit to show that it is the active connection. There should be no other connections to the transformer.

12) Press the Trigger control key to initiate the measurement. Figure 5-15, above, will be displayed while high voltage is applied to the measurement terminals and the measurement result will be displayed.

13) Press the Sec–GND soft key and, if necessary, re-establish the measurement conditions outlined in steps 6) and 7).

14) Connect the Secondary BROWN BNC connector to one end of the transformer secondary winding. Connect the GREEN CLIP LEAD to the transformer metal case or screen The

LED above the Secondary BROWN BNC connector should be lit to show that it is the active connection. There should be no other connections to the transformer.

15) Press the Trigger control key to initiate the measurement. Figure 5-15, above, will be displayed while high voltage is applied to the measurement terminals and the measurement result will be displayed.