Shimaden PAC18 Series, Инструкция по эксплуатации

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16-3. If using magnetic switch (contactor)
If using a magnetic switch (contactor) for a circuit connected to the transformer (inductive load), malfunction could result from contact bounce.
If so, you should either use the prescribed noise filter, or connect an X capacitor (0.1 – 0.5 µF) between the R and U power supply side terminals of the
thyristor, or a Y capacitor (1000 – 3300 pF) between the R and U power supply side terminals and the ground to absorb the noise.
Power
supply
Load
(heater)
PAC18
R U
Transfor mer
Magnetic switch
transformer
16-4. Rapid fuse usage
We recommend a rapid fuse to protect the thyristor device from excessive current produced when using a transformer due to high frequency wave noise or
load trouble, etc.
16-5. Prohibition of operating without load
Before conducting operation whereby a load cannot be connected such as test operation, disconnect the transformer wiring and connect a dummy load such
as an electric heater or light bulb. Do not operate the device with the secondary side of a transformer load open.
Do not switch loads while the device is powered. Doing so could result in excessive current due to failure of the soft start function to be triggered or the
protective circuit to be triggered due to absence of a load.
Example: If using a single heater and it becomes broken, then the device would be operating without a load.
16-6. Complex control phase angle adjustment
Select complex control if you want to use a single phase transformer as a load for cycle calculation zero voltage switching control.
Phase angle adjustment is required for complex control.
With complex control, slow-up is conducted by phase control ahead of cycle calculation zero voltage switching control to cancel magnetic flux imbalance
of single phase transformers.
If however a sine wave of single phase transformer primary and secondary side current that is negatively and positively symmetrical is not present,
magnetic flux imbalance could be produced, resulting in excessive current.
It is therefore necessary to adjust load current so that negative and positive are symmetrical in order to cancel magnetic flux imbalance.
After presetting load conditions of the transformer actually used, adjust while monitoring load current. Phase angle is adjusted so the current waveform is a
non-sine wave. Adjust by key sequence ‘1-2. Complex control phase angle adjustment.’
This adjustment could produce excessive current; increase load current gradually while monitoring the current waveform.
17. Parameter setting function / Communication
17-1. Parameter setting function (optional)
If the device is optionally equipped with a parameter setting function, you can connect to a computer via a separately sold data communication
adapter and display various settings, control input values, output values and trend graph.
17-2. Communication (optional)
Hardware conforms to RS-485.
Communication protocol is MODBUS (RTU).
Set communication conditions by ‘key sequence 1-14. Communication address,’ ‘key sequence 1-15. Communication speed,’ ‘key sequence 1-16. Communication
parity,’ ‘key sequence 1-17. Communication Stop bit’ and ‘key sequence 1-18. Communication delay.’
For details, see the instruction manual for the communication interface.
Current produced by magnetic flux imbalance
After adjustment
Load current waveform