MIB Installation Instructions and Reference Handbook
DEIF A/S
Page 15 of 50
Measuring connections
The MIB can be used in almost all kinds of 3-phase connections.
The voltage and current input wiring modes can be set separately in the
parameter setting process. The voltage wiring mode can be:
The rated measuring voltage of the MIB is 400 LN and 690V
LL. Naturally, the instrument can be used in systems with
lower system voltage level, e.g. in connection with 100V volt-
age transformers. The measuring accuracy will in this case be
slightly reduced. The voltage range of PT1 is 50-1.000.000V.
Voltage inputs
• 3LN: 3-phase 4-line Y
• 2LN: 3-phase 4-line Y with 2 voltage transformers
• 1LN: 1-phase 2-line
• 3LL: 3-phase 3-line direct connection
• 2LL: 3-line open delta
The MIB is designed to be used together with current trans-
formers with secondary output of 5A. If the secondary cur-
rent is 1A, the primary ratio has to be multiplied with 5 to
give a correct reading.
Example: 500/1 = 2500/5.
Max. transformer ratio: 50000/5 or 10000/1.
Current inputs
• 3CT
• 2CT
• 1CT
Any voltage mode can be grouped with any of the current modes.
The wire of the measuring inputs supply should be 1.5-5mm²
(AWG10-16). The voltage measuring inputs should be pro-
tected by fuses (1A/250V AC).
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