Weidmuller G438 Ultra SlimPak - Manual (Page 3)

A major advantage of the G438 is its wide ranging capabilities and ease of configuration.
For example, in a valve positioning application a potentiometer is sometimes used as a feedback signal.
Quite often a wide open valve is only a 25% turn of the feedback potentiometer. In this case the G438 can
easily be adjusted with the zero and span to provide a full scale output signal (e.g. 4-20mA) representing
0-25% or even 50-75% of the potentiometer input.
Unless otherwise specified, the factory presets the Model G438 as follows:
Input Range: 0 to 100%
Output: 4 to 20mA
The DC power input accepts any DC source between 9 and 30V; typically a 12V or 24Vdc source is used.
For other output ranges, refer to Tables 1 and 2 to reconfigure switches SW1 and SW2 for the desired input
and output ranges.
Do not attempt to change any switch settings with power applied. Severe damage will result!
1. With power disconnected, set the output and input switch selectors (SW1 and SW2) to the desired
ranges (Tables 1 and 2).
2. Connect the input and output as shown in wiring diagram. Connect the output to the actual device load
(or a load approximately equivalent to the actual device load value) and apply power.
NOTE: To maximize thermal stability, final calibration should be performed in the operating installation,
allowing approximately 1 to 2 hours for warm up and thermal equilibrium of the system.
3. Set the input potentiometer to the desired minimum and adjust the zero potentiometer for the desired
minimum output.
4. Set the input potentiometer to the desired maximum and adjust the span potentiometer for the desired
maximum output.
5. Repeat steps 3 and 4, if necessary, for best accuracy.
Configuration
WARNING
Calibration
INPUT
ZERO
SPAN
ULTRA
SLIMPAK
G438
Output (+) Output (-)
DC Power (+)
52
21
11 12
22
41
51
42
DC Power (-)
_
_
Potentiometer Input
(full counter clockwise)
Potentiometer Input
(wiper)
Potentiometer Input
(full clockwise)
Shield Ground
52 51
42 41
12 11
22 21