Simple fan coil wiring diagram - In a regular extent fan motor, approximately 60 of the power fed on is used to move the air, leaving 40 or much less of the energy ate up to turn the motor. While the fan motor has a mechanical failure or belt breakage the motor amperage drops kind of 60.
Fan coil devices placed out a much lower air volume than packaged air managing units, making dp switches unwanted due to low accuracy at low air float charges. So in preference to degree float the use of differential strain, an installer can reveal the amperage draw at the motor to determine its operation reputation.
The technology is powerful, however it has drawbacks. Dp switches are mechanical, and, therefore, require habitual service. Clogged tubing and pitted or corroded contacts make the switch not able to respond to an alarm circumstance. Moreover, the select-up tubes are outside, and can be challenge to damage in the course of installation of the fcu. Sooner or later, general enterprise dp switches do not always have enough sensitivity to monitor structures with low air go with the flow, consisting of the ones found in fan coil units.
Present day switches screen fan motor status with the aid of analyzing the amperage inside the conductor supplying the motor. A mechanical failure within the motor causes a drop in amperage this is right away detected by using the modern switch, which sends an alert to the manage gadget. Modern switches offer the maximum dependable and price effective manner to display fine proof of waft for fan automobiles in fan coil units (fcus).
Differential strain (dp) switches display fan motor repute by sensing the difference in strain between the deliver and discharge facets of the fan. This is carried out via penetrating the duct paintings and putting in pick out-up tubes on both sides of the fan. The tubing is hooked up to a mechanical switch that has a single adjustable ride point. When a change in the differential pressure between the choose-up tubes is detected, the transfer opens or closes as a result.