Installation
Connecting Load Cells
VT300 Technical Manual, Rev. A4
21
Doc
#
TM-VT300-EN
2.3.2
Wall-Mount Model (Stainless Steel)
Use 6 x 0.5mm
2
shielded cable for load cell connections. Connect the load cells
according to the diagram below.
Figure 4 – Load cell connection diagram for wall-mount model
2.3.3
Load Cell Operating Parameters
The load cell utilization ranges are listed in the table below.
Excitation
5VDC, fixed or alternating polarity (setup-selectable) for 10 load cells of 350
Ω
each.
Gain / input ranges
•
For load cell output of 10mV, gain permitted is between -0.25 and 1.75mV/V.
•
For load cell output of 20mV, gain permitted is between -0.25 and 3.75mV/V.
The load cells must be chosen so that the input signal to the controller is at
least 0.4µV per scale increment. For load cell output less than 0.4µV/digit, the
controller will still be stable but the full temperature range accuracy is not
guaranteed.
Do not run signal cables together with power cables. Connect the shielding only
where indicated in the drawing. Never use a Megger to check wiring. Never use
plastic insulating tape on load cell connections.
+
POWER
¯
JP1
+
INPUT
¯
OUT1
OUT2
COM
TX
RX
SGND
SHIELD
+ SIG
– SIG
+ EX
+ SEN
- SEN
- EX
PCB 801
PCB
765
SHLD
+SIG
–SIG
+EX
+SEN
–SEN
–EX
7
6
5
4
3
2
1
7
6
5
4
3
2
1
7
6
5
4
3
2
1
3
2
1
