09/ 2019
BENNING CM E1
14
7.1 Loop resistance ranges
Measuring range
Resolution
Measurement accuracy
*1
0.025 Ω - 0.250 Ω
0.002 Ω
± (1.5 % ± 0.05 Ω)
0.251 Ω - 1.000 Ω
0.02 Ω
± (1.5 % ± 0.05 Ω)
1.001 Ω -10.00 Ω
0.02 Ω
± (1.5 % ± 0.1 Ω)
10.01 Ω - 50.00 Ω
0.04 Ω
± (2.0 % ± 0.3 Ω)
50.01 Ω -100.0 Ω
0.04 Ω
± (2.0 % ± 0.5 Ω)
100.1 Ω - 200.0 Ω
0.4 Ω
± (3.0 % ± 1.0 Ω)
200.1 Ω - 400.0 Ω
2 Ω
± (5.0 % ± 5 Ω)
400.1 Ω - 600.0 Ω
5 Ω
± (10 % ± 10 Ω)
600.1 Ω - 1500 Ω
20 Ω
± (20 %)
*1
valid for purely ohmic resistances, external magnetic field <30 A/m, external electric field <1 V/m
Measuring frequency: 3.333 kHz
Accuracy of the reference resistance loop: approx. ± 1 %
Alarm threshold
Range
Resolution
Upper alarm (HI)
0 - 1510 Ω
1 Ω
Lower alarm (LO)
0 - 1510 Ω
1 Ω
7.2 AC current/ leakage current
The measured value is obtained and displayed as real r.m.s. value (True RMS, AC coupling). Its calibration
is adapted to sinusoidal curves. In case of deviations from this curve shape, the accuracy of the displayed
value decreases. Crest factor < 3.5
Measuring range
Resolution
Measurement accuracy
in frequency range 50 Hz - 60 Hz
0.300 mA - 1.000 mA
0.001 mA
± (2.0 % ± 0.05 mA)
1.00 mA - 10.00 mA
0.01 mA
± (2.0 % ± 0.03 mA)
10.0 mA - 100.0 mA
0.1 mA
± (2.0 % ± 0.3 mA)
100 mA - 1000 mA
1 mA
± (2.0 % ± 3 mA)
0.200 A - 4.000 A
0.001 A
± (2.0 % ± 0.03 A)
4.00 A - 35.00 A
0.01 A
± (3.0 % ± 0.03 A)
Overload protection: 100 A
8. Measuring with the BENNING CM E1
8.1 Preparation for measuring
Operate and store the BENNING CM E1 at the specified storage and operating temperatures only! Do not
permanently expose the device to sunlight.
- Strong sources of interference in the vicinity of the BENNING CM E1 might involve unstable readings
and measuring errors.
8.2 Loop resistance measurement
Do not exceed the maximum permitted voltage with respect to earth potential!
Electrical danger!
- Open the measuring clamp and check whether the metallic contact surfaces inside the clamp are free
of dust and contamination.
- Let the jaws of the measuring clamp snap together several times (open and close them) in order to
establish a safe contact.
- Use the rotary switch
3
to select the function
Ω
(loop resistance) or
Ω
+ (loop resistance with alarm).
Wait until the end of the self-calibration (CAL 7, CAL 6, ..., CAL 2, CAL 1) is confirmed by an acoustic
signal and the “.OL” symbol appears on the digital display
B
.
