AERCO Electronic Controls System (ECS) - Manual (Page 25)

Electronic Control System (ECS) and Type CXT-E Valve
3. ADJUSTMENT
VD2: 02/28/14 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288 Page 25 of 82
AC-105 OMM-0003_0D
3. ADJUSTMENT
3.1 INTRODUCTION
This Section provides adjustment procedures for both the Control Valve, Type CXT-E and the
Electronic Control System (ECS).
Prior to shipment, from AERCO, all CXT-E Control Valve Actuators are adjusted (auto-stroked)
to ensure that they properly position the Control Valve from the fully-open to the fully-closed
positions. In addition, the ECS is adjusted to the Setpoint Temperature specified on the Sales
Order. If no setting was specified, the default is 140°F.
It is recommended that the following procedures be performed to the extent necessary, prior to
placing the system into operation. Also, the applicable procedures MUST be performed
following replacement of the CXT-E Control Valve or other ECS components. In addition, the
following procedure must be performed following maintenance or adjustment of linkage,
actuator or packing nut.
CAUTION
As a precaution, ensure that all heating fluid (steam or hot
(boiler) water) shutoff valves are fully closed prior to performing
any of the following adjustment procedures.
3.2 CONTROL VALVE TYPE CXT-E ADJUSTMENT
All CXT-E Actuators are powered by 24 VDC and are controlled by a linear 4-to-20 mA control
signal. A 4 mA control signal input places the Control Valve in the fully-closed position(Valve
shaft down); while a 20 mA signal strokes the Valve to the fully-open position (Valve shaft up).
The Control Valve Actuators are self-calibrating for all Valve sizes. Therefore, simply proceed as
follows to automatically adjust the Actuator:
NOTE:
The following adjustment procedure must be performed any time that
the CXT-E Actuator is replaced or a mechanical adjustment is made
to the Linkage Assembly or Valve.
1) Refer to Figure 3-1 and loosen the Actuator cover set screw.
2) Remove the Actuator cover to access the PC Board containing the terminal connections,
DIP switches, Auto-Stroke (Reset) button and LED shown in Figure 3-1.
NOTE:
When properly connected to the ECS, +24 VDC power is supplied to
the Control Valve Actuator when the Control Box POWER switch is
set to the ON position. This switch is located on the right side of the
Control Box.
3) Set the ECS Control Box POWER switch to the ON position to apply 24 VDC power to the
Actuator (pin 2 = +24 VDC, pin 1 = Common). The LED will light indicating that power is
applied.
4) Wait approximately 10 seconds while the unit performs a self-test. The LED will blink from
one to four times depending on the size of the valve as follows:
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