Dual-Level Reservoir Sensor 
Part # 30-3221-2 
 
Dual-Level Reservoir Sensor 
The Dual-Level Reservoir Sensor is designed for use in the brine-
filled reservoir of the interstitial area of a  double-walled tank. This 
sensor contains a dual-level float switch that detects level changes of 
fluid in the reservoir of the tank. The sensor expects the liquid to be 
at a constant level. The system will activate the alarm when the brine 
level in the interstitial space either rises or falls. 
It can also be used in other areas (such as dispenser containment 
pans) that are normally dry and will give a low-level warning followed 
by a high-level alarm. In the event of a break in the cable, the system 
will activate the alarm. 
 
 
 
 
 
 
 
*NOTE: Maximum Wiring Length is the maximum length of cable to 
be used to connect all sensors on an individual channel. This length 
includes run of cable from I.S. Barrier to each sensor board in the 
string.