Operating instructions

23
NOTE FOR LOAD MONITORING:
Load threshold I 35LSB
Load threshold U 35LSB
If a Thyro-P 3P is used in phase-angle operating mode, the star point of the load and the star point
of the (built-in) voltage transformers should be connected together to ensure an accurate load
monitoring. Please contact us in case of need..
The values in the following table apply to ohmic loads.
Different values apply may be required for specific heating resistors, for instance IR radiators.
The adjustable % values shown in the tables are load current variations on the present operating
values.
NOTE
Values < 10% should be chosen carefully because it
can cause wrong error messages, e.g. due to strong
fluctuations in mains voltage.
HEATING 1P 2P*/3P 3P
ELEMENTS
IN PARALLEL FOR
EACH STRAND STAR CONNECTION STAR CONNECTION DELTA STAR CONNECTION
WITH SEPARATE WITHOUT CONNEC- CONNECTION WITH CONNECTED
STARPOINTS TED NEUTRAL NEUTRAL
CONDUCTOR CONDUCTOR
5 10% 10% 8% 6% 10%
4 13% 13% 10% 7% 13%
3 17% 17% 13% 10% 17%
2 25% 25% 20% 12% 25%
1 50% 50% 50% 21% 50%
* for Thyro-P 2P: additional external converters in phase L2 are possible.
Star connection
with separate star points
Star connection
without neutral conductor
TAB. 2 PARTIAL LOAD BREAKDOWN WITH HEATING ELEMENTS SWITCHED IN PARALLEL,
UNDERCURRENT, RELATIVE MONITORING
Delta connection
Star connection
with neutral conductor