Institute of Power Electronics
and Electrical Drives
Prof. Dr.-Ing. Jörg Roth-Stielow
Current probe ILA SMZ 200: Operating instructions and technical data
1. Operating instructions for the Current probe ILA SMZ 200:
The current probe ILA SMZ 200 is an instrument for non-contacting measurement of currents with any
waveform and amplitudes up to ± 250 A. (For overload capability see technical data). Conductors of the
primary current (the current to be measured) have to be isolated.
At the amplifier's coaxial output cable a signal voltage proportional to the measured current is put out. If
a 50Ω terminating resistor (2W) for the coaxial cable is used, the proportionality factor is 10 mV A .
The amplifier's ground conductor is connected to the amplifier's case as well as to the protective
conductor of the probe's mains-plug.
If the current probe shall be connected to a display instrument whose ground potential must not be
connected to the mains' protective conductor, the probe has to be supplied by an isolating transformer
and without connection to the mains' protective conductor. Attention! In that case, special care has to be
taken by the user to prevent persons from touching the amplifier's case.
In some cases, the quality of the signal voltage's waveform can be improved by additionally connecting
the amplifier's ground conductor to the ground conductor of the display instrument. For that purpose you
will find a 4 mm socket connector at the amplifier's front panel.
Immediately after switching on the probe, degaussing and offset-correction takes place automatically.
The duration of this event is about 2 s. It is displayed by a green LED at the amplifier's front panel.
During degaussing and offset-correction the current sensor must be kept close and no current-carrying
conductor must be in the sensor's window.
Degaussing and offset-correction can also be triggered manually by pressing the small knob under the
note "Entmagnetisieren" at the amplifier's front panel. Manual degaussing may be necessary after
overloading the probe or after a considerable change of temperature inside the amplifier.
Datasheet ILA SMZ 200
2
The current sensor's magnetic circuit consists of two ferrite-cores, one U-shaped and one I-shaped.
These cores can be damaged due to a considerable mechanical stress. Hence, a negligent treatment
such as throwing, letting it fall down or use as a mechanical tool is not permissible.
Attention!
The current probe ILA SMZ 200 is sensitive
to mechanical shock, so it must be treated carefully!
Datasheet ILA SMZ 200
3
2. Technical Data of the Current probe ILA SMZ 200:
- AC/DC Current Range:
IN (Max. continuous current with
o
o
ambient temperature 25 C, which is 77 F)
200 A
- Max. Current:
Max. Peak Current Imax
o
o
(For Th ≤ 50 C/122 F, where Th = temperature
of amplifier heatsink)
250 A
- Accuracy:
Offset-Error right after degaussing (rated to IN)
< 0.5 %
Linearity-Error for |I| ≤ Imax (rated to IN)
< 0.5 %
- Dynamic characteristics:
di
Measurable dt
> 1500 A/μs
Propagation delay
< 20 ns
Leakage inductivity
< 45 nH
- Output characteristics:
10 mV/1A
Output voltage to current ratio at 50 Ω/2W in
line BNC-Termination
- Power Supply:
Power supply
Max. Power consumption
Fuse
230 V ± 10 % / 50 Hz
40 VA
200 mA, inert
- Input overload indication
- Degaussing facility
- Current sensor:
Window area for primary conductor
(Length x height)
Width
Covering material of the sensor
- Total weight (Sensor and amplifier)
9 x 9.5 mm2
(0.35" x 0.37")
15 mm (0.59")
Terluran 969 T(ABS)
approx. 2.4 kg (5.3 lbs)
On request a model for 110 V/60 Hz power supply is available. This one must be fused with 400 mA,
inert.
Datasheet ILA SMZ 200
4
Fig. 2
Current probe ILA SMZ 200
Fig. 3
Sensor of the Current probe ILA SMZ 200
Datasheet ILA SMZ 200