User guide

5
Introduction
Instrument/Sensor System Diagram
1.4 System Diagram
SENSOR CABLES
RG-59/U COAXIAL
150 FEET MAXIMUM LENGTH
FRONT PANEL
MODEL 187
LIQUID LEVEL
CONTROLLER
REAR PANEL
SOLENOID-OPERATED
FLOW VALVE
(OPTIONAL)
LIQUID REFERENCE
PLATE CAPACITOR
VAPOR REFERENCE
PLATE CAPACITOR
CONCENTRIC-TUBE,
CAPACITANCE-BASED
PROBE
MAXIMUM
MEASURED
SPAN
MINIMUM
ZERO
OFFSET
Figure 1-1. Model 187 instrument, control valve, and sensor system diagram.