Cinergia GE+ - Case External Isolation Transformer with or Without Inrush Current Limitation Box; Option A: with Inrush Current Limitation Box; Option B: Without Inrush Current Limitation Box

GE+ ACDC Installation and operation manual v11
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3.4. Case External Isolation Transformer with or without inrush current
limitation box
Following the recommendations from the transformer manufacturer, the recommended
protection for the primary (grid) side of the transformer is a moulded circuit breaker type D
rated current.
Please note that the isolation transformer presents a high inrush current due to the
magnetizing of the transformer core. If this inrush current trips an upstream circuit
breaker we recommend installing an inrush current limitation box.
In case to install an isolation transformer, it is recommended to install an insulation
monitor relay, to detect and recognize insulation faults in a IT system.
3.4.1. OPTION A: WITH INRUSH CURRENT LIMITATION BOX
Following Spanish regulations, the recommended protections and wires are:
 Grid side RCD – A indicated on diagram page 3: 300mA, type B, > rated current (as
indicated on table below)
 Grid side MCB – C indicated on diagram page 3: Rated current, type C
 Wire from grid to transformer primary – W3 indicated on diagram page 3: wire W3
indicated on table below, 3 phase + neutral + PE. The size of PE cable will depend on
local regulations and electrical system (TN, TT, IT, etc…)
The above recommended protections are useful in case that CINERGIA provides the
transformer. In case that a third party supplies the transformer, please follow the
recommendations from the transformer manufacturer.
From transformer secondary to CINERGIA equipment input (grid side)
 MCB, rated current – B1 indicated on diagram page 3, type C
 Wire from transformer secondary to GE input – W2 indicated on diagram page 3: wire
indicated on table below, 3 phase + neutral. The size of PE cable will depend on local
regulations and electrical system (TN, TT, IT, etc…)
From CNG equipment output to Equipment under test:
 Wire indicated on table below – W2 indicated on diagram page 3: 3 phase + neutral (in
AD mode) or 3 phase + 3 negative common (in DC mode). The size of PE cable will
depend on local regulations and electrical system (TN, TT, IT, etc…)
Please, check that the above recommendations fulfil with your country or zone
regulations.
3.4.2. OPTION B: WITHOUT INRUSH CURRENT LIMITATION BOX
Following Spanish regulations, the recommended protections and wires are: