Application Example Using Load Cells - Mettler Toledo PANTHER Guide D'installation

METTLER TOLEDO PANTHER Panel-Mount Terminal Division 2 Installation Guide
Application Example
Using Load Cells
2-4 (7/03)
The following is an example of applying the PANTHER terminal in a Division 2 application
connecting a model 2158 Vertex floor scale with 50 feet of load cell cable. The field circuit
parameters for all devices and cables in the load cell line (including the load cells and
junction box) must also be known.
Terminal model:
Base model:
Load cell model:
Quantity of load cells:
Load cell cable length:
Junction box PCB p/n:
PANTHER field circuit parameters from control drawing 155907R:
V = 5.5 VDC
t
I = 166 mA
t
C = 590 µF
a
L = 1.3 mH
a
Load cell field circuit parameters from 745A load cell control drawing:
V = 25 VDC
max
I = 600 mA
max
C = 0 µF
i
L = 29 µH
i
Load cell cable default values from PANTHER terminal control drawing 155907R:
C p= 60 F / foot
cable
L = 0.2 µH /
cable
foot
The 2158 junction box PCB was determined to not have significant capacitance or
inductance impact. Values shown below should be used.
C = 0 pF
i
L = 0 µH
i
PANTHER terminal (Division 2 approved)
2158 Vertex (with Division 2 approved cells)
METTLER TOLEDO 0745A
4
50 feet
13640300A