Siemens SENTRON PAC4200 Manual page 73

Protecting the current measuring inputs
Electric shock and arc flashover in the case of open transformer circuits
Will cause death, serious injury or considerable property damage.
It is only possible to measure the current with external current transformers. The circuits
must NOT be protected with a fuse here! Never open the secondary circuit of the current
transformers under load. Short-circuit the secondary current terminals of the current
transformer before removing the device. The safety information for the current transformers
used must be followed!
Protecting the voltage measuring inputs
Damage to the device due to non-fused voltage measuring inputs
Damage to the device and the equipment may occur.
In the case of a direct connection and transformer connection, the device has to be
safeguarded with an approved (UL / IEC) 10A backup fuse or an approved (UL / IEC) 10 A
miniature circuit breaker.
When using voltage transformers, their secondary connections must never be short-
circuited.
SENTRON PAC4200
Manual, 09/2008, A5E02316180B-01
DANGER
CAUTION
Connecting
6.2 Connections
73