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. 6 / 8
ADJUSTMENT PROCEDURE
Remove the cover.
Manipulate ZERO, SPAN, DZ (deadband), and DLY (Re-
starting timer) adjusters and the direct/reverse SW on the
control PCB shown in Figure 3.
Other adjusters which are paint-sealed are for factory use
only and should be changed only by qualified M-System per-
sonnel. Otherwise it could cause breakdown. M-System is
not liable for any malfunction or inconvenience caused by
unauthorized changes made by the user.
■
DIRECT/REVERSE ACTION AND OPERATION AT AB-
NORMALLY LOW INPUT
The actuator action is factory set to “Reverse” (i.e. the out-
put stem goes up as the input signal increases.), and the
operation at abnormality to “Go down.”
For changing the setting, use the DIP SW on the control
PCB referring to Tables 2 and 3.
Table 2. Switching Actions
ACTION
SW1-3
EXPLANATIONS
Direct
ON
Output stem goes up as the input
signal decreases.
(Valve stem extended)
Reverse
OFF
Output stem goes down as the
input signal decreases.
(Valve stem retracted)
Table 3. Operations at Abnormally Low Input
OPERATION
SW1-1
SW1-2
Stop
– *
1
ON
Go down/Extend
OFF
OFF
Go up/Retract
ON
OFF
*1. The setting of SW1-1 is disregarded in Stop mode.
Note 1: SW1-4 is not used.
Note 2: In ‘Direct’ action, the position output is 5 – 1V DC
proportional to the input 0 – 100%.
■
ORDER OF ADJUSTMENTS
After installation, perform adjustments in the order
of: zero; span; seal-spring; and sensitivity (deadband).
Lastly, adjust the limit switches for optional full-open and
full-closed signals.
The following explanation applies to ‘Reverse’ action.
For ‘Direct’ action, read the values in the brackets [ ].
Note: Applying an over-torque to the adjusters may dam-
age the threads or destroy stoppers. Use a small-sized
screwdriver and be sure to stop turning as soon as they
hit the stoppers.
■
ADJUSTMENT PROCEDURE
A) Zero and Span
• Supply power voltage to the MSP and apply 0%
[100%] input. Turn Zero adjuster to adjust the
lower-end or fully-extended position of the output
stem (valve stem retracted) to a desired position.
Alternatively, adjust the connecting section of the stems.
For applying a sealing pressure, refer to Table 4 and
screw it until the opening equals the contraction that cor-
responds to the sealing pressure.
• While applying 100% [0%] input, turn the Span adjuster
until the output stem reaches a desired upper-end or ful-
ly-retracted position (valve stem extended).
For three-way valves, the sealing pressure can be applied
also in the direction in which the output stem goes up*
2
.
Refer to the procedure for Zero adjustment.
• While applying 0% [100%] input again, check that
the output stem reaches the fully-extended position.
If the position is shifted, go through the above procedure
again.
Note 1: The MSP is designed so as to minimize an influence of
Span adjustment on the Zero position.
That is, the lower-end position of the output stem is
hardly displaced when Span adjuster is manipulated.
Note 2: Narrower stroke is more likely to cause hunting
i.e. the motor frequently changes rotation direction.
Adjust Deadband in such a case.
*2. MSP4 is not provided with a sealing spring for the direc-
tion in which the output stem goes up.
Seal-Spring Division
Output Stem
Figure 9. Seal-Spring
Table 4. Spring Contraction
MODEL
SPRING
CONTRACTION
(mm)
SEALING
PRESSURE
(N / lbs)
SET LOAD *
(N / lbs)
MSP4-x3
0.5
147 / 33
98 / 22
MSP4-x4
1.0
300 / 67
250 / 56
MSP4-x7
1.0
686 / 154
294 / 66
MSP5-x3
0.5
150 / 34
110 / 25
MSP5-x4
1.0
294 / 66
216 / 49
MSP5-x7
1.0
686 / 154
294 / 66
MSP6-x3
1.0
588 / 132
441 / 99
MSP6-x4
1.0
1170 / 263
882 / 198
MSP6-x6
1.5
2350 / 529
1170 / 263
* The pre-set load for applying a minimum pressure to seal the
valve when the valve sits on the seat.
Note: The output stem is provided with a scale in millimeters.
In case of MSP4-x7, for example, the sealing pressure
reaches approx. 490 N at 0.5 mm and 686 N at 1 mm.
