SanRex CALPOTE UG Series, Instruction Manual, Page: 9 / 97

9
2 PRECAUTIONS DURING USAGE
Pay attention to the following when using the unit.
 The main circuit thyristor may be damaged in short circuit mode. To prevent fire and
property damage in case of ground faults, ensure that the design is safe by, for example,
installing protective functions on the power input side of the unit main circuit using breakers
or other devices.
 It is not recommended to operate this product while switching the output between 0% and
100% at intervals of a few minutes repeatedly. The main circuit thyristor will reach the upper
limit of the power cycle, breaking down earlier than specified. Reduce the output variation
range, select a model with sufficient capacity for the rated current, or take other measures
to prevent the early breakdown.
 To wire the main circuit, use cables with sufficient capacity for the rated current of the unit.
 To wire the main circuit, connect the K terminal to the power supply side and the L terminal
to the load side.
 Be sure to match the phases of the main circuit power supply and the control circuit power
supply.

Do not bundle the control circuit cables together with the main circuit cables.

When storing the unit in the distribution panel cabinet, provide ventilation in consideration of
the internal calorific value of the unit.
(See “9 UNIT OUTLINE” for the internal calorific value.)

Note that dust, moisture, overheating, vibration, and other issues may degrade the
performance of the unit or cause it to fail.

Be sure to install the unit upright and vertical and keep space around the unit as instructed
in the installation precautions. Installing the unit horizontally or reducing the space may
degrade the cooling performance, and may lead to abnormal high temperature.

Install the unit so that its front door can be opened and closed for maintenance or
inspection.

When operating the unit with cycle control, it is preferable to use a fuse-attached model of
the unit.

The unit cannot be operated with cycle control with inductive loads. Be sure to operate the
unit with phase control when inductive loads are applied.
(Contact us for customized products.)

If the load capacity is small, a leakage current is applied to the load side even when the
signal is off, causing malfunctions. To prevent this, connect a bleeder resistor in parallel with
the load. (The minimum load current is 1 A.)

If the load capacity is small (approximately 10% of the rated capacity or lower), error code
Er.14 is displayed with the self-diagnostic function. This, however, does not cause any
problems during operation.

Do not apply 5 V or more or 20 mA or more from the temperature controller.