The C.W.T. External Loop Interface Explained

What is a C.W.T. External Loop Interface?

The ClearWater Tech, LLC. External Loop is a true dry contact interface designed to allow main power of the ozone generator to remain “ON” while only energizing or de-energizing the ozone reaction chamber(s). The term “dry contact” means the loop does not supply output nor except input voltages.

The function of the external loop is to interface the ozone generator to any control device. Some devices include:

• Pressure switch
• Vacuum switch
• Flow switch
• Float switch
• ORP controller
• PPM monitor
• Ambient ozone monitor
• Timer (both digital & analog)

How Does it Work?

Under normal operation the external loop will effectively interrupt the ozone output when the loop has lost continuity. When continuity through the external loop is restored, ozone output will continue.

Removable Dry Contact Loop

For continuous operation (not using an external control device),  a removable two-position plug with an 18AWG wire loop is supplied with the ozone generator. As long as the loop remains closed, ozone production will remain constant.

To interface a control device to the external loop, simply cut the 18AWG wire in half. Connect the control device to each leg of the external loop and you now have on/off control of your ozone generator’s ozone production. If the control device used supplies an output voltage, a single pole single throw (SPST) normally open relay may be used to create a dry contact interface (see diagram below).

The External Loop Interface

Warning: Supplying voltage to the external loop will not only cause damage to the ozone generator, but it will void the warranty as well.

-Authored by Brandon Turney, Service Technician, ClearWater Tech, LLC