The Model 3920 uses a 2 or 3-wire resistive temperature detector to provide a proportional 4-20 mA Analog current output. The 3920 boards are enclosed in an oval extruded aluminum protective housing.
The Barton Model 3920 is available in four configurations for application flexibility:
EM Version: "Electronics module" onsisting of a circuit assembly (two printed circuit boards) enclosed in a protective cast aluminum housing with external controls for span and zero adjustments.
WL Version: “Wall-mount” version of the EM module; two metal flanges for wall or surface mounting.
Hazardous Location: Two-piece cast aluminum alloy explosionproof enclosure (available in indicating and blind versions). The EM module is held in place within the enclosure by a spring clip.
RF Unit Option: Additional protection for Radio Frequency (RF) interference is offered as an option on the EM or WL modules. This is not normally offered on a hazardous location model since the aluminum shell of the Hazardous Location enclosure offers inherent RF shielding.
On the EM module, the standard input connector is replaced by an alternate input connector that contains a printed circuit board and the filter. Dimensionally, a RF equipped module is approximately 10 mm (3/8") taller.