A very important part of calibration of the V100 and V200 is setting the cam properly. If the cam is not set properly the result will be either the positioner will not span out (fail to reach 100% of the range), or the positioner will get full range but the user will not be able to get the positioner to output a linear response to set-point signal. The other issue maybe that the cam nut is not tight causing the positioner to go all the way to span with very little input signal.
Reminder: Before Cam setup, ensure the actuator is in the zero position.
On initial setup of the V100 or V200 it is important to look to see if the cam is set up with the cam tip (3) close to the roller bearing (4) on the positioner. Once the cam nut is tight (1) and set screw tightened (2), put air to the positioner. Then once the air is on, press down on the balance arm. By doing so, we exhaust air to the actuator causing the positioner to move the valve package. When the valve package begins to move the cam will rotate. At this point we can determine if our cam setup is correct. If the cam rotates up and over the cam tip (3) we know the cam must be removed and flipped over. If the cam rotates away from the tip (3) we know that the cam is set correctly.
Our engineer has been working hard over the last few years to develop our very own I/P for the V200 series (pictured above right). We have started to receive the first of the new I/Ps in some of our latest shipments and we couldn’t be more excited for this development. The performance of the VAC I/P is better than the older unit used (pictured above left). The sound is a bit different on the VAC I/P since the exhaust of the I/P is located in a different spot than our previous I/P. The bleed rates between the old and new I/P are very comparable. If you have any questions please give us a call at (205) 678-0507 or email Scott Kratz or Matt Dill.