Figure. 5.6.1. - 171. System in case when primary phase current wiring is broken.
In this case all other conditions are met except the residual difference which is now 0 x In and thus
indicate primary side fault.
Figure. 5.6.1. - 172. System in case of primary side high impedance earth fault.
In case of high impedance earth fault the CTS will not activate if the measurement conditions are met
and the calculated and measured residual current difference is not reaching the limit. The setting Isum
difference should be set according to the application to reach maximum security and sensitivity for the
network earthing.
Events and registers
The CTS function generates events and registers from the status changes of the ALARM activated and
blocked signals. To main event buffer is possible to select status “On” or “Off” messages.
Function includes 12 last registers where the triggering event of the function (ALARM activated or
blocked) is recorded with time stamp and process data values.
Table. 5.6.1. - 220. Event codes of the CTS function instance
Event Number
Event channel
Event block name
Event Code
Description
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
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