Liquid Controls LCR Install - Manual (Page 9)

9
Valve Installation
General
The LCR can provide security valve and preset control
capabilities via the Solenoid 1 and 2 outputs. Single-
stage and two-stage solenoid actuated valves and three-
way solenoids can be controlled. Valves should be
installed in accordance with accepted industry practice
and Weights & Measures regulations. NOTE: The
modulated two-solenoid valves designed for use with the
LectroCount3 cannot be used with the LCR.
LPG and NH3 Truck Installations
The differential valve used on many LPG trucks can be
used in conjunction with Liquid Controls 3-way solenoid
kit as a security valve. Since the differential valve is
installed after the meter, little of the piping has to be
modified.
The 3-way solenoid mounts to the LCR via the rear middle
port using the short 1/2” NPT nipple and explosion proof
union supplied with the kit. Port A is connected to the
vapor eliminator’s vapor port. Port B is connected to the
differential valve’s diaphragm. Port C is connected to
upstream system pressure. See illustration below.
If the solenoid is not energized by the LCR, upstream
high pressure liquid is directed to the valve diaphragm
and the valve closes, preventing product from being
delivered.
When the solenoid is energized by the LCR’s SOL-2
signal, the vapor eliminator’s control port is connected
to the differential valve. This allows the valve to function
normally: if the vapor eliminator is filled with liquid, the
pressure on the valve (bonnet) is low and the valve opens,
allowing product to be delivered. If the fluid level in the
vapor eliminator drops, high pressure gas will be directed
to the valve bonnet, and the valve will close.
NOTE : Liquid Controls’ supplied 3-way solenoids can
have either of two labeling schemes. Check to determine
which 3-way solenoid has been supplied with your kit.
Install as indicated below.
Port Connections:
A (or R)
- connected to air eliminator vapor port.
B (or B) - connected to valve diaphragm.
C (or P) - connected to upstream system pressure.