Division 2 Application Example Using Load Cells - Mettler Toledo IND570 Série Guide D'installation

be safe. If the AIT of the hazardous product is lower than the temperature rating of the IND570xx
terminal, the IND570xx terminal MUST NOT BE USED in that environment.
2.8.

Division 2 Application Example Using Load Cells

The following is an example of applying the IND570xx terminal in a Division 2 application
connecting a model 2158 Vertex floor scale with 50 feet of load cell cable. The non-incendive field
wiring circuit (NIFW) parameters for all devices and cables in the load cell line (including the load
cells and junction box) must also be known.
IND570xx load cell NIFW parameters from control drawing 30116036:
Load cell NIFW parameters from model 745A load cell control drawing:
Default load cell cable values from IND570xx terminal control drawing 30116036:
30205321 | 05 | 03/2019
THE IND570xx TERMINAL HAS A TEMPERATURE RATING OF T5 (100° C) FOR GAS AND A MAXIMUM
SURFACE TEMPERATURE RATING OF 85° C FOR DUST. IT MUST NOT BE USED IN AREAS WHERE THE
AUTO IGNITION TEMPERATURE OF THE HAZARDOUS MATERIAL IS BELOW THIS RATING.
Note: There are many methods that may be used to install properly approved equipment within
hazardous areas. In our example, the non-incendive field circuit parameters (electrical approval
data) were compared to those of the load cells connected to make sure the combination is
safe. In other applications (specifically in Europe), only a confirmation of a certain IP rating
and maximum surface temperature may be required to connect the devices.
Terminal model: IND570xx terminal
Base model: 2158 VERTEX
Load cell model: METTLER TOLEDO 0745A
Quantity of load cells: 4
Load cell cable length: 50 feet
Junction box Model: AJB641SX
V / U
oc o
I / I
sc o
C / C
a
L / L
a o
V = 25 VDC
max
I = 600 mA
max
C = 0 µF
i
L = 29 µH
i
METTLER TOLEDO IND570xx Division 2 and Zone 22 Installation Manual
WARNING
®
(with approved cells)
= 10.5 VDC
= 304 mA
= 1 µF
o
= 0.6 mH
2-9