iSMA CONTROLLI MVH Series Mounting Instructions

MVH ACCESSORIES
Valve Actuators
MVHPA: Cards With 1 kΩ Auxiliary Potentiometer
• Open the cover.
• Disconnect the cables on the terminal board and the cable connectors of the motor and, if any, of the electromagnet (spring
return version).
• Unscrew the fastening screws (1) from the electronic card.
• Remove the existing electronic card.
• There are white and grey gears in the package; use the white ones for 25-45 mm stroke and the grey ones for stroke up to
25 mm.
• Assemble the small gear (3) on potentiometer shaft (4) of the auxiliary card, after inserting ring (5) on wheel (3).
• Insert the card with the auxiliary potentiometer taking care that the pins on the support enter in the corresponding holes (2)
on the electronic card.
• Restore the electrical connections.
• Insert firmly retaining ring (6) on large gear (7).
• Bring the potentiometer up to the stop by rotating the shaft counter-clockwise.
• Insert gear (7) on the hexagonal shaft until it collides with the electronic card so that its toothing engages with gear (3) (in case
this latter operation does not go through, turn gear (3) upside down).
• After the actuator has run a complete 45 mm stroke, the potentiometer has 0 Ω between W3 and W2 and 1000 Ω between W2
and W1 when the actuator is at the lower stroke end (joint down). It has instead 1000 Ω (see table) between W3 and W2 and
0 Ω between W2 and W1 by upper stroke end (joint up). To state the resistance max. value among the potentiometer terminals
refer to the table below.
Variation is 22,22 Ω for every mm stroke upwards both in increase between W2-W3 and in decrease between W2-W1.
The performances stated in this sheet can be modifi ed without any prior notice.
MOUNTING INSTRUCTIONS
Stroke [mm] Wheel colour
16,5 Grey
25
White
45
www.ismacontrolli.com
Aux. potentiometer max. value
1000 Ω
700 Ω
1000 Ω
DIM163en | 1 Issue | 07/2022
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