If you have a good operational R-57 vacuum system on your SA-200 and want to upgrade it to automatically release from idle when using a grinder or when you strike an arc, and don't want to go through the expense of replacing the whole idle control system, this is for you.
The Weldtron-UI idler module is now offered with an optional power resistor that will upgrade your old R-57 without the need to replace any linkage or add any solenoids. It is an inexpensive way of upgrading in lieu of spending hundreds more to modernize a working operational vacuum system.
Since parts are no longer available for R-57 idlers, the day will come that when the vacuum diaphragm or solenoid will fail and then more good news is in order. You only have to add the solenoid that is used on our Weldtron-57 idler upgrade, make a bend in the existing throttle linkage and you upgrade your machine to a new electrical system. All that you have to do is to wire the machine as shown in the Weldtron-R57 idler upgrade, discard the resistor and use the Weldtron-UI that you have already installed.