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8. Inductive and Transformer Coupled Load
Guidelines
9. Firing (Trigger) Mode Overview
8.1 Notes: Use with inductive loads and transform-
ers
1. when the CFW is working it is not allowed to open
neither the connection between CFW and the trans-
former nor the connection between the transformer
and the load
2. The maximum current controllable by the device is
less than the product’s rated value (see technical
data).
3. In ZC and BF trigger mode, use the Delay-triggering
function to limit peak magnetization current.
4. In PA trigger mode, use the Softstart function.
5. DO NOT use HSC trigger mode.
6. DO NOT connect RC snubbers in parallel to the
transformer primary.
7. Always set Dip-Switch 5 to ON (and run the initial
configuration procedure as described.
9.1 Trigger Modes
The CFW has the following power control modes:
• modulation via variation of number of conduction cycles with zero crossing trigger.
• modulation via variation of phase angle.
Zero Crossing mode
This function eliminates EMC noise. This mode controls power on the load via a series of conduction ON and non
conduction OFF cycles.
ZC - constant cycle time (Tc
≥
1 sec, settable from 1 to 200 sec)
Cycle time is divided into a series of conduction and non conduction cycles in proportion to the power value to be
transferred to the load.
For example, if Tc = 10sec, if the power value is 20% there is conduction for 2 sec (100 conduction cycles @ 50Hz)
and non conduction for 8 sec (400 non conduction cycles @ 50Hz).
BF - variable cycle time (GTT)
This mode controls power on the load via a series of conduction ON and non conduction OFF cycles.
The ratio of the number of ON cycles to OFF cycles is proportional to the power value to be supplied to the load.
Summary of Contents for CFW
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