Watson Smith Type 421 I/P Converter

Please be advised that this model has now been made obsolete by Watson Smith and it is therefore no longer available.

You will find below our suggestion for a suitable Watson Smith replacement unit.

Watson Smith Type 421

Specifications:

Input signal: 4-20mA (two wire)
Output: 0.2 to 1bar (3 to 15psig); minimum outlet pressure less than 15mbar (0.2psig). Also available 0.4 to 2 bars.
Air supply: Oil free, dry air, filtered to 5 microns; 1.5 to 3.5bar (20 to 50psig) or at least 0.7bar
above maximum output pressure
Port size: 1/8” NPT female
Failure Mode: Faisafe (Signal falls to below 15mbar (0.2psig) when input signal fails)

Suitable replacement

In most cases the Watson Smith type 100X I/P converter is the most suitable replacement for the Type 421. The only major difference is in the shape of the unit itself. The Type 421 was designed to be mounted on DIN rail.

To help with this the type 100X can be fitted with a DIN rail adaptor (please contact us for more information). However we strongly advise to check the dimmensions prior to purchase.

Are you looking for a new Watson Smith item, a replacement or just some advice? Not sure where to start? As the top UK distributor for Watson Smith we can help!

Just send us an enquiry or call us now on 01202 480 303 or email us at sales@coulton.com !