Licht
http://www.licht-labs.com
Rev. A2 (23–01–09)
MFC-200/P Technical Manual
13
6 Error conditions
6.1 Synchronism error
Synchronism errors occur whenever one or more Follower on-load tap changers stop fol-
lowing their Master, despite commands to do so. These may occur between 3-phase
transformers or phases of a 3-phase group of monophase transformers.
Synchronism errors are only set after the user-configurable Syncronism Timeout expires.
Possible causes:
.
Connection failure between the raise/lower voltage regulator and the tap changer.
.
Tap changer failure, preventing it from receiving and/or executing position changes.
.
An Individual transformer is incorrectly configured as Follower.
.
The position was manually altered at the tap changer and not through the paral-
lelism controller.
6.2 Position deviation
Position deviations are characterized by readings which shift considerably from their ideal
value. Despite not being large enough to be interpreted as another position altogether,
they suggest failure or imminent failure of the position transducer element, either due to
calibration, tap changer failure or connection problem.
Possible causes:
.
EMI (electro-magnetic interference) due to faulty or lack of cable shielding.
.
EMI due to failure to ground the cables’ shielding.
.
Shielding grounded at more than one point.
.
Contact problem.
.
Failure to recalibrate after changing cables.
6.3 Configuration error
Configuration errors may occur in the following scenarios:
.
Follower channels without a Master.
.
Master channel with no Followers.
.
More than one Master.