Switch On
When the probe is switched on to the required measuring range, the green LED will illuminate. The LED starts flashing when the battery voltage is too low for normal operation and
warns the user that it requires changing. This procedure is described below.
Auto Power Off
In order to save battery life, the probe will automatically switch itself off after approximately 10 minutes. To disable the Auto power off function, Switch off the probe and Switch on whilst pressing the auto zero button. The red LED will illuminate and the probe will stay on until switched off again.
Auto Zero
The output zero offset voltage of the probe may change due to thermal shifts and other environmental conditions. Select the required measuring range and to null the output voltage
depress the Auto Zero button. Ensure that the probe is away from the current carrying conductor whilst the probe is being nulled.
Current Measurement
1. Switch on the probe by selecting the required measuring range and check that the green LED is lit.
2. Connect the output lead to the oscilloscope,
3. Zero the probe using the Auto Zero button.
4. Clamp the jaws of the probe round the conductor ensuring a good contact between the closing faces of the jaws.
5. Observe and take measurements as required. Positive output indicates that the current flow is in the direction shown by the arrow on the probe.
Battery Replacement
The green or red LED will flash when the minimum operating voltage is approached. Use the following procedure:
SAFETY WARNING
Before removing the battery cover, ensure that the probe is disconnected from the oscilloscope and remote from any live electrical circuit.
Unclamp the probe from the conductor, turn it off using the On - Off switch and disconnect the output leads from external equipment.
Loosen the captive screw which secures the battery cover. Lift the cover through 30° and pull it clear of the probe body as shown in Fig 1. Replace the battery, re-fit the battery cover and fasten the screw.
Fit only Type 9 V PP3 Alkaline (MN 1604).
