Flowserve DFP17 - Manual (Page 9)

WCAIM2037 DataFlo Digital Electronic Positioner DFP17 Installation, Operation and Maintenance Instructions 9
3.2 Input Signal Connections
NOTE: The Digital Positioner signal input circuit is protected by a 1/16
amp fuse, F1 (See Figure 2 and Section A of Section 1.1).
See Section 5.2 for input circuit specifications.
After input signal connections have been made, securely tighten all
terminal screws. Keep wiring away from all rotating parts and ensure
it will not be pinched when the actuator cover is installed.
3.2.1 Milliamp
DFP17-1, DFP17-4, DFP17-10 (Milliamp Input Signal for
Digital Positioner)
For a milliamp signal input, the more positive or “High”
signal lead should connect to actuator terminal 11. The
less positive or “Common” lead should connect to actuator
terminal 10. (Terminal 10 is (-), Terminal 11 is (+).)
This positioner is available for use with the standard
milliamp signals: 1 to 5, 4 to 20, and 10 to 50 milliamps.
The positioner board is factory calibrated for one of the
three milliamp signal ranges. A label on the circuit board
indicates the positioner’s signal range.
Section 5.4 gives the nominal resistance load, which the
positioner presents to the control circuit for the three
signal ranges.
Comparison of resistance measurements made at
terminals 10 and 11 (on the yellow and blue wires from
the circuit board) against the resistances shown in part
5.4 provides a quick way to determine the milliamp range
for which a particular board is calibrated. If fuse F1 is
blown, an open circuit will be indicated.
NOTE: If the circuit board has an orange wire attached to
it (See Figure 2), the board is set up for a Potentiometer
Input. See section 3.2.2 and Figure 3.
3.2.2 Resistive
DFP17-13, DFP17-1K (Potentiometer Input for Digital
Positioner)
NOTE: The Input Potentiometer is not the Feedback
Potentiometer, but is an additional potentiometer
provided by and externally located by the end user.
For a potentiometer input signal, the usual connections
will be similar to that shown in Figure 3 with a “Close”
command being generated when the potentiometer of
Figure 3 is rotated to its full CCW position and an “Open”
command when it is in the full CW position.
If the command signal is derived from other than a rotary
pot, it is only necessary to keep in mind that a “Closed”
(full CW) valve is called for when the command
potentiometer presents the least resistance between
terminals 10 and 11 and the most resistance between
terminals 11 and 12. A full “Open” (full CCW) valve
would be the reverse condition; the least resistance
between terminals 11 and 12 and the most resistance
between terminals 10 and 11.
If the “Command” potentiometer is reasonably linear, the
actuator/valve will be approximately 50% open when the
potentiometer shaft is halfway through its travel and the
resistances between terminals 10 to 11 and 11 to 12 are
equal.
Potentiometer input circuit boards are made in two
versions, one for high resistance command circuits -
1000 ohms nominal, and one for low resistance
command circuits - 135 ohms nominal.
3.2.3 DC Voltage
DFP17-5V, DFP17-XV (Direct Voltage Input Signal for
Digital Positioner).
For a voltage input signal, the more positive or “High”
signal lead should connect to terminal 11. The less
positive or “Common” lead should connect to terminal 10
[Terminal 10 is (-), Terminal 11 is (+)]
This positioner is available for use with the standard
direct voltage signals: 0 to 5 VDC and 0 to 10 VDC. The
positioner board is factory calibrated for one of these two
signal ranges and field changes are not advised.
Section 5.4 gives the nominal resistance load which the
positioner presents to the control circuit for the two
signal ranges.
Flow Control
Worcester Actuation Systems
Figure 3