Performing Current Measurements - Conrad 12 87 40 Bedienungsanleitung

Used batteries are to be treated as waste requiring special hand-
ling and must therefore be disposed of without harming the en-
vironment. Special collection bins are provided for this purpose
at specialist retailers and in waste-recovery yards.
5.2 Connecting the instrument leads
For measurements, always use only the Current Clamp Adapter
captive connecting cable. Before connecting, always check the
condition of the BNC connecting plug and check the insulation
for damage. Connect the plug to the BNC input socket of an os-
cilloscope (channel 1 or 2). Set the oscilloscope input coupling
switch (AC-GND-DC) to DC and the input amplifier sensitivity of
the respective channel to 5 mV/division or lower (if possible). This
setting of input sensitivity is not required with oscilloscopes ha-
ving an automatic setup function.

6. Performing current measurements

Attention!
Under no circumstances exceed the maximum permitted input
levels 600 A DC / A AC rms max. At the same time, the voltage
may never exceed 600 V DC or 480 V AC rms! Touch no circuits or
circuit components where voltages higher than 25 VAC rms or
35 VDC can be present! Danger to life!
To measure direct or alternating currents, procedure is as follows:
1. Switch the Current Clamp Adapter and the connected oscillos-
cope on. Set the oscilloscope AC-GND-DC coupling to "DC"
and the "V/division" switch to 5 mV (or lower).
2. Open the current clamp with the clamp opening lever. Enclose
not more than one insulated conductor during DC current
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measurements; when measuring AC current, enclose only one
insulated cable in a single-phase system or only one or several
insulated cables of a multiphase system.
Attention!
Just below the clamp opening is a hand protector, a plastic ridge.
While enclosing the cable or current rail and during measure-
ments, never grip beyond the hand protector - DANGER TO
LIFE!!!
3. Close the clamp around the current-carrying cable by releasing
the clamp opening lever. The contact surfaces of the clamp
must be securely closed; the cable(s) must move freely within
the clamp opening. Ensure that the cable is positioned as cen-
trally as possible during the reading.
4. During DC measurements the direction of current flow is im-
portant. If the oscilloscope beam moves downwards, then the
direction of the current has probably been misjudged.
5. Before measuring DC current, the indication on the oscillosco-
pe must be set to "zero". For this, set the AC-GND-DC switch to
GND and with the vertical position control of the selected
channel adjust the beam to coincide with the horizontal cent-
re line. Then set the AC-GND-DC switch to DC once again. Now
adjustment of the Current Clamp Adapter to "0" can be car-
ried out. Turn the "ZERO ADJUST" control until the beam coin-
cides with the horizontal centre line of the oscilloscope.
Attention!
During calibration, no conductor may be within the current
clamp and the clamp may not be close to a magnetic interferen-
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