Siemens SIWAREX WP241 - Connecting the load cells

Connecting
6.2 24 V connection
SIWAREX WP241
26 Manual, 04/2014, A5E33713528A
6.2
24 V connection
The 24 V DC supply voltage is connected by means of the corresponding terminals on the
electronic weighing system.
Table 6- 1 Connection of the 24 V supply
Labeling
Function
L +
+24 V voltage supply
M
Ground voltage supply
6.3
Connecting the load cells
Overview
Pickups can be connected to the SIWAREX WP241 electronic weighing system which are
equipped with strain gauges (full bridge) and meet the following requirements.
● Characteristic value 1 to 4 mV/V
● A supply voltage of 5 V is permitted
● Maximum cable length between WP241 and junction box 1 000 m
The power supply for the load cells is 4.85 V.
The following condition must be satisfied in order to check the maximum possible number of
load cells which can be connected to a WP241:
● Scale operation without Ex interface: (input resistance of load cell) / (number of load cells)
> 40 Ohm
● Scale operation without Ex interface: (input resistance of load cell) / (number of load cells)
> 50 Ohm