Emerson Daniel 788DVC User Manual page 14

Introduction
October 2019
Figure 1-2: Open - control position
Open position (no control)
The normally closed solenoid is open. The normally open solenoid is closed. Y-port (P3) is
open to Z-port (P2). X-port (P1) is closed off by the normally open solenoid. The pressure
on the bottom of the piston (P1) is greater than the pressure at (P3) plus the spring force;
(P1 minus P2) is equal to or greater than the spring force. Therefore, (P1) pressure pushes
the piston open. No flow control is required. (See below.)
14
User manual
P/N 3-9008-556
Model 788DVC Digital Control Valve