Emerson Fisher FIELDVUE DVC7K Series Quick Start Manual page 34

DVC7K Digital Valve Controllers
October 2023
Configure the unique parameters for the actuator, instrument, and accessory construction. Select if factory defaults
should be applied.
3. Relay Adjustment (Relay A only)
If the digital valve controller has a Relay A (for double-acting or single-acting direct applications) and needs a relay
adjustment, you will be led through a guided Relay Adjust method. For double-acting actuators, the valve must be
near mid-travel to properly adjust the relay.
Note
A label affixed to the relay itself will specify the relay type.
Relay B (for single-acting reverse applications) and Relay C (for single-acting direct applications) are calibrated at the factory and
requires no further adjustment.
Rotate the adjustment disc, shown in figure 4‐1, until the output pressure displayed is between 50 and 70% of supply
pressure. This adjustment is very sensitive. Be sure to allow the pressure reading to stabilize before making another
adjustment (stabilization may take up to 30 seconds or more for large actuators). If the low bleed relay option has
been ordered stabilization may take approximately two minutes longer than the standard relay.
Figure 29. Relay A Adjustment (Shroud Removed for Clarity)
ADJUSTMENT DISC
W9034
Note
Care should be taken during relay adjustment as the adjustment disc may disengage if rotated too far.
34
FOR SINGLE‐ACTING DIRECT
RELAYS: ROTATE ADJUSTMENT
DISC IN THIS DIRECTION UNTIL IT
CONTACTS THE BEAM
FOR DOUBLE‐ACTING RELAYS:
ROTATE ADJUSTMENT DISC IN
THIS DIRECTION TO DECREASE
OUTPUT PRESSURE
FOR DOUBLE‐ACTING RELAYS:
ROTATE ADJUSTMENT DISC IN
THIS DIRECTION TO INCREASE
OUTPUT PRESSURE
Quick Start Guide
D104766X012