1. PRESENTATION
The oscilloscope clamp measures DC or AC currents, without opening the circuit they are flowing in. The
current clamp is used as an accessory for multimeters, recorders, etc.
This clamp measures DC currents up to 600 A and AC currents up to 400 A rms (600 A peak). It outputs
the form and amplitude of the current measured as a voltage image of the primary current.
The clamp has two ranges, 40 A (sensitivity 10 mV/A) and 400 A (sensitivity 1 mV/A), a zero adjust push
button, auto off feature to economise the battery power supply and two light indicators, one for faults
(over-range / incorrect zero reset), the other for power supply.
2. DESCRIPTION
See descriptive diagram at the end of the User Manual.
➀ Passage of the conductor
➁ Jaws
➂ Protective non-slip guard
➃ Automatic zero DC button
➄ Red fault light (over range / incorrect zero adjustment)
➅ Green light indicating correct power supply
➆ 3-position sliding switch (off / selection of 1 mV/A or 10 mV/A ranges)
➇ Hand-held parts
➈ Fitted lead 1.5 m
➉ BNC plug
3. OPERATING PROCEDURE
3.1. SWITCHING ON
Set the sliding switch ➆ to the appropriate position, 40 A range (sensitivity 10 mV/A) or 400 A range
(sensitivity 1 mV/A). Correct operation is indicated by a green light ➅ indicating that the battery is in
good condition.
After approximately 10 minutes of operation of the clamp without manipulation of the control buttons, the
power supply cuts off automatically (see " Auto off " below).
If this green indicator does not come on when the clamp is switched on, or goes out before it has operated
for 10 minutes, it is necessary to replace the battery.
3.2. DC ZERO ADJUSTMENT
Ensure that the jaws of the clamp are correctly closed and that they do not enclose any conductor. Connect
the clamp to your measurement instrument. Press the auto zero button ➃. The red light ➄ comes on
for approximately three seconds to indicate that the instrument is on zero calibration. If zero can not be
obtained, this indicator light remains lit to indicate the fault.
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