Emerson Process Management El-O-Matic E and P Series E25-E950 Benutzerhandbuch

Seite 43

Advertising
background image

16

DOC,F20,EDN Rev.: -

4.1

Electrical Connections

Connect the 4 - 20 mA signal to the terminals (4) and (5),
making sure that the + and - are the correct way round. The
voltage is ~8 VDC.

4.2

Initial Setup - Zero, Range and Sensi-

tivity

The factory settings provide the positioner with an initial range
of settings that will allow the operation of positioners on most
applications.

Signal Input

- 4 mA. - 20 mA.

Range

- 0% to 100%

Control Function

- Linear.

Action

- Direct Acting.

(CCW with increasing Signal).

Three settings are provided on the main circuit board. These
allow adjustments of the zero, range and dead band (sensitiv-
ity).
Before making adjustments the positioner should be already
mounted on the valve/actuator, air supply connected, and a 4 -
20 mA.(¯8V.) signal connected to the signal input terminals.

4.3

Zero Setting

The zero resetting trimmer on the circuit board is marked
“Zero”. To change the position for the 4 mA signal, first set the
signal to 4 mA, then turn the trimmer screw until the desired
position is reached.

4.4

Range Setting

The positioner range is limited by the stroke position at the 20
mA. signal point. The range resetting trimmer on the circuit
board is marked “Span”. To change range, first set the signal to
20 mA, then turn the trimmer screw until the desired position is
reached.

4.5

Sensitivity Setting

A setting that is too high will cause the positioner to “hunt” with
difficulty in establishing a settled output. A setting that is too low
causes an output that is sluggish and lacking in response.
The sensitivity resetting trimmer on the circuit board is marked
“Damp”. To change sensitivity, first set the signal to an approxi-
mate mid point between 4 and 20 mA, then turn the trimmer
screw until the best result is reached.

Note:
The trimmers operate clockwise (CW) to increase, counter
clockwise (CCW) to decrease.

4.0

Electrical Connections and settings / Elektrische Anschlüsse und Einstellungen /

Elektrische aansluitingen en instellingen

Damp
Zero
Span
Input signal
Positioner coil
Feedback
potentiometer

= Empfindlichkeit
= Nullpunkt
= Bereich
= Eingangssignal
= Festspule
= Rückmelde-

potentiometer

= Gevoeligheid
= Nulpunt
= Bereik
= Ingangssignaal
= Standsteller Spoel
= Terugmeld

potentiometer

Positioner coil

Feeback potentiometer

Span

Zero

Damp

-

4-20 mA
(~8 VDC Input signal)

+

Advertising
Dieses Handbuch ist für die folgenden Produkte bezogen werden: