[SM-206790-A/5]
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OPERATION
5
5.4 Electric Circuits
a) Check for the presence of any current leak from the
external control device because it may cause an er-
roneous valve operation.
When a programmable controller or a similar control de-
vice is used, a current leak may prevent the normal re-
turning of the valve when the solenoid is de-energized.
b) Restriction on current leak
When controlling solenoid valves using a programmable
controller or a similar control device, make sure that the
current leak in the programmable controller output is
equal to or less than the level shown in the table below.
A current leak larger than the allowable level may cause
an erroneous valve operation.
(1) With a double solenoid type valve system, energize the solenoid for at least
0.1 second even for an instantaneous valve operation. If the target valve
can be affected by a back pressure induced by another solenoid valve, it is
recommendable to energize the solenoid as long as the cylinder is making an
action.
(2) If solenoids are energized for a prolonged period of time, the surface temper-
ature of the manifold will rise. Through this increase in the temperature
should not be regarded as abnormal, provide a suitable means of ventilation
or heat release.
!
CAUTION :
AC100V
3.0 mA or lower
AC200V
1.5 mA or lower
DC24V
1.8 mA or lower
CR circuit
Leakage
current
Solenoid valve
Contact
C
R
Programmable
controller