VAC V100 Troubleshooting Manual

Trouble Shooting Guide for V100 Positioner

1)  1.V100 not responding to input signal

a) The tubing to the actuator may be

  incorrect

  i)   Plant Air Supply should be ported to

      the Sport on the side of the 

      positioner. Supply must be 

      greater than 30 PSI.

  ii)  The pneumatic control signal 

      (3 to 15 psi) should be ported to 

      the Ip port on the side of the 

      positioner. 

      If the positioner is a V100E, using 

      an I/P on the positioner, the Ip

      port should be plugged tightly!! Double check once plug is in place to make sure 

      there is no air leakage from Ip plug.

  iii)  The driving port of this positioner is the C+ port. In other words, on an

      increasing control signal the supply is directed through the positioner to the

      C+ port. This is very important – not only for single acting 

      or spring assist valve packages, but also to insure proper

      air to open (or close) operation (rotation).

b) I/P wiring

  i)   Make sure the unit is properly wired.

      (1)  The positive terminal (+) MUST have a positive 

voltage to it.

    (2) The negative terminal (-) MUST have a negative voltage to it.

c) I/P operation

  i)   If the I/P has been in use the potential for contaminated air 

      supply exist – check the I/P by either of the following steps.

  (1)  Install a gauge on the I/P gauge port (1/8 inch NPT) to make 

      sure that the I/P is generating a 3 to 15 psi pneumatic output in correlation to

      the 4 to 20 mA input signal.

  (2)  Using an ohm meter check to make sure that there is resistance still in the

      loop. A good unit will put out 240 Ω or more.