Resistance Measurement
Model 5895 Transformer Micro-Ohmmeter
This Micro-Ohmmeter, type 5895, has been specifically designed for the fast measurement of the resistance of large transformers. It is equally suitable for the measurement of any resistance where a large amount of inductance is also present. An integral timer and printer are also incorporated to enable precise readings to be recorded at exact and programmed time intervals. Whilst being practical in use the instrument also has safety features to protect both the operator and the instrument from the hazards associated with this type of measurement. This instrument is suitable for the resistance measurement requirement of BS171 Part 2 or Part 1 IEC 76-5.
IEEE-488 Interface included as standard.
Speed of Measurement
Stable accurate measurements can be achieved in a fraction of the time required than when using more traditional bridge methods. For an average size distribution transformer the resistance reading is available within 10 seconds.
Typical Reading Times |
10 Seconds |
11KV, 220 KVA Transformer |
40 Seconds |
132 KV, 240 MVA Transformer |
100 Seconds |
400KV, 220KVA Transformer |
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Method of Operation
A high test current and unique circuitry is used to rapidly drive the core into saturation and to eliminate any oscillation of the magnetic field, thus enabling a steady reading to be obtained quickly. A large high intensity LED is illuminated when the instrument is in the "Read" mode and remains ON when the instrument is switched to "Zero" until any E.M.F.'s, generated in the transformer as the magnetic field collapses, have fallen to a safe level for the leads to be removed.
Specifications
See the table below for a run-down of this product's specifications.
Range |
Full Scale |
Resolution |
Test Current |
Accuracy |
100Ω |
180.00 Ω |
10 µΩ |
0.1 Amps |
0.1% |
10Ω |
18.000 Ω |
1.0 µΩ |
0.5 amps |
0.1% |
1Ω |
1.8000 Ω |
0.1 µΩ |
1.0 Amps |
0.1% |
100µΩ |
180.00 µΩ |
10 µΩ |
5.0 Amps |
0.1% |
10µΩ |
18.000 µΩ |
1 µΩ |
5.0 Amps |
0.1% |
10µΩ |
1.8000 µΩ |
0.1 µΩ |
10 Amps |
0.2% |
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Supply |
110/120 V 50/60 Hz |
220/240 V 50/60 Hz |
VA Rating |
500 VA |
Dimensions |
460 x 460 x 150 mm |
Net Weight |
16.5kg |
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