MSP4 / MSP5 / MSP6
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: [email protected]
EM-4854 Rev.15 P. 2 / 8
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YOKE DESIGN
• When a foreign object is caught in the valve, a thrust 4
times greater than the maximum rating could be gener-
ated. Leave enough strength for mechanical components
such as the yoke and the valve stem.
• If the MSP is used in an application such as temperature
control of a steam line, the temperature can rise higher
than the ambient temperature due to heat conducted or
radiated from the piping even when the ambient temper-
ature is within an allowable range.
Use a longer yoke to increase heat dissipation and apply
insulating material.
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AND ....
• DO NOT loosen the screw fixing the potentiometer lever.
Loosening it could cause a malfunction.
• DO NOT step onto the actuator.
• DO NOT allow a heavy object to rest on or against the
actuator.
PROTECTIVE FUNCTIONS
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OVERLOAD (LOCK) PROTECTION
The MSP is equipped with a protection circuit against over-
load caused by, for example, valve catching an alien sub-
stance.
When an overload is detected, the MSP stops supplying
power to the motor and the status LED blinks at 0.5 sec.
intervals.
The protection can be reset by applying an input signal to
move the output stem in the opposite direction, or turning
power off and restarting.
If the overload (lock) protection is activated too often, check
for the presence of foreign matter in the valve, inappropri-
ate adjustments, excessive tightening of the valve gland, or
other possible causes of the overload.
Be sure to remove the cause of overload in order to avoid
shortening the life of the product.
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FUSE
A fuse is equipped for protection against overload current.
Ensure that the power LED turns on as the power supply
is turned on. If the power LED remains off, check to see if
the fuse is melted. Replace the melted fuse with a new one.
If the new fuse is melted again soon after replacement,
there may be problems with the control PCB or the motor.
Consult M-System or sales representative.
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RESTARTING TIMER
The MSP is equipped with a timer circuit for setting a time
interval (0 – 10 sec.) between stop-restart actions to prevent
the motor and other internal components from overheating.
It is recommended to set the restarting timer longer when
the ambient temperature and/or the temperature of flow
material is high.
The restarting timer is factory-set to 1.5 sec.
