Showa Denki Mistresa CRH Series, Operation Manual

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(3) Using the burnout prevention terminals
The CRM-S, CRM-V, and CRMH-S Series Mistresa have a heat-sensitive
thermal protector at the motor winding. This auto reset thermal protector
operates as follows. When the motor winding temperature rises
excessively high, the relay contacts open. When the temperature comes
back down to a certain temperature, the contacts automatically close
again. Connect the thermal protector with the terminals A and B for
burnout prevention.
By connecting this terminal in series with the operating circuit of the
electromagnetic switch (with thermal relay), to prevent motor burnout.
CAUTION
①
Be sure to connect the "A" and "B" terminals to the operation circuit
in order to protect the motor.
②
Use the prescribed or lower contact rating (115V AC, 18A / 230V
AC, 13A / 24V DC, 18A).
③
When the thermal relay is tripped, correct the cause, then press the
[RESET] button.
④
The thermal relay may be erroneously tripped if the Mistresa is operated
in an intermittent manner. In this case, change the thermal relay.
a) Connection example for burnout prevention terminals "A" and "B"
Electromagnetic switch device (with thermal relay) Please prepare.
Power supply
When using
an electromagnetic
switch
Terminal box
Thermal protector
THR MC
THR MC
ON OFF
MC