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BENNING CM 1–4
7.3 AC current ranges
Measuring
range
Resolution
Measurement accuracy
in frequency range 45 Hz - 65 Hz
Overload
protection
200 A
0.1 A
± (3.0 % of r 7 digits)
200 A
7.4 Resistance measuring ranges
Measuring
range
Resolution
Measurement accuracy
Overload
protection
9999 Ω
1 Ω
± (1.5 % of r 7 digits)
1000 V AC/DC
50.00 kΩ
0.01 kΩ
Measuring voltage: approx. 0.5 V
7.5 Continuity test
The integrated buzzer sounds at a resistance R lower than approx. 1.8 kΩ to
2.7 kΩ.
Acoustic indication: signal of 2.7 kHz
Optical indication:
-LED
Response time:
<100 ms
Open-circuit voltage: approx. 0.5 V
Overload protection: 1000 V
AC/DC
7.6 Single-pole external conductor test
(phase indication)
Sensitivity:
90 V to 1000 V (voltage to earth) in earthed mains
Frequency range: 45 Hz - 65 Hz
Acoustic indication: signal of 2.7 kHz
Optical indication:
-LED
7.7 Phase sequence test
Sensitivity:
90 V to 1000 V (voltage to earth) in earthed mains
Frequency range: 45 Hz - 65 Hz
Optical indication:
-LED,
-LED
8. Measuring with the BENNING CM 1-4
8.1 Preparation for measuring
Operate and store the BENNING CM 1-4 at the specified storage and operating
temperatures only! Do not permanently expose the device to sunlight.
- Check stated nominal voltage and nominal current on the safety measuring
leads. Nominal voltage and current of the enclosed safety measuring leads
comply with the respective values of the BENNING CM 1-4.
- Check insulation of the safety measuring leads. If the insulation is damaged,
the safety measuring leads must be replaced immediately.
- Check the safety measuring leads for continuity. If the conductor in the safety
measuring lead is interrupted, replace the safety measuring leads immedi
-
ately.
- Attach the protective caps (CAT III/IV) to the contact tips before making
measurements in circuits of overvoltage category CAT III or IV.
see fig. 1b: Using the protective caps
- The rear holder of the BENNING CM 1-4 is intended for attaching the mea-
suring leads for voltage measurement and when not in use/for storage.
see fig. 1c: Measuring leads holder
- Strong sources of interference in the vicinity of the BENNING CM 1-4 might
involve unstable readings and measuring errors.
8.2 Self-testingfunction(self-test)
After each switch-on via the Ω/A key
6
or the HOLD key
7
, the BENNING CM 1-4
carries out a self-test. An acoustic signal is emitted and all display segments and
LED indications must light up briefly.
If the self-test detects an abnormal behaviour, the device must be switched off
immediately and secured against unintended operation.
Before and after using the BENNING CM 1-4, check the function of the voltage
measurement and the single-pole external conductor test (phase indication) at a
known voltage source.