Grounding And Bonding; Installation Procedure - Mettler Toledo Division 2 IND570 Serie Guia De Instalacion

In addition to the formulas above, the temperature rating of the IND570xx terminal must be checked
against the AIT (Auto Ignition Temperature) of the hazardous product. For this example, the
hazardous product has an AIT of 200°C (393°F), which is higher than the rating of the IND570xx
terminal approval value of 85°C (203°F) for dust and 100°C (211°F) for gas. This indicates the
temperature comparison test passes.
Since all four NIFW parameters compare favorably and pass the formula evaluation and the
temperature comparison test passes, the products listed in this example may be safely installed into
a Division 2 area. All equipment must be installed according to their corresponding control drawing
using all pertinent local and national codes and regulations.
2.9.

Grounding and Bonding

All grounding (earthing) and equal potential bonding connections must be made according to local
regulations based upon the country of installation. Refer to local codes and the control drawing or
installation drawing in the Appendix section of this manual for more specific information regarding
grounding. It is typical that regional regulations require that all connected pieces of equipment in
the system be bonded together and grounded to a single point. Wire loops, external screws and
star washers have been provided in the installation accessory kits of each terminal to assist in field
installation. Figure 2-5 indicates the locations for grounding and bonding connections on the
panel-mount and harsh enclosure terminals.
2.10.

Installation Procedure

Once the information in this chapter and in all other suggested regulatory documents has been read
and understood, the IND570xx terminal may be installed. Refer to Chapter 2 of the IND570
2-10 METTLER TOLEDO IND570xx Division 2 and Zone 22 Installation Manual
L + L ≤ L / L
i cable a o
L = 29 µH (load cells) = 0.029 mH
i
L = 0 µH (junction box)
i
L = 0.2 µH / foot * 50 feet = 10 µH = 0.01mH
cable
(0.029 mH + 0 mH + 0.01 mH) ≤ 0.6 mH
Figure 2-5: Grounding Points, Panel-mount (left) and Harsh Enclosure (right)
Formula Pass or Fail
PASS
30205321 | 02 | 05/2017