Hazardous Area Classification; Pollution Degree Specification; Protection Approaches - Mettler Toledo IND780 Guia De Instalacion

If so marked, the IND780 terminal has been approved for use in areas classified as Division 2 or
Zone 2 or Zone 22. This approval DOES NOT mean that the IND780 terminal can be used in
Division 1, Zone 0 or Zone 1 areas. Different precautions must be taken when installing equipment
into these areas. Please consult your local METTLER TOLEDO representative regarding applications
in a Division 1, Zone 0 Zone 1, Zone 20, or Zone 21 area.
The Category 3 marking of the IND780 permits use of the IDNet version with Category 3 approved
"T-brick" versions of the High Precision base within Zone 2 and Zone 22 areas.
1.1.

Hazardous Area Classification

A hazardous (explosive) area is classified as a Division 2 area when the hazard is either not
present during normal operating conditions or is present only for very short periods of time.
A hazardous (explosive) area is classified as a Zone 2 area when an explosive gas-air mixture is
METTLER either not present during normal operating conditions or is present only for very short periods of
time.
TOLEDO DOES
NOT CLASSIFY
A hazardous (explosive) area is classified as a Zone 22 area when an explosive atmosphere, in
HAZARDOUS
the form of a cloud of combustible dust in the air, is either not present during normal operating
AREAS!
conditions or is present only for very short periods of time.
The area must be classified by an agent of the customer.
1.2.

Pollution Degree Specification

The terminal's Pollution Degree is 2.
1.3.

Protection Approaches

Various protection methods are used by different manufacturers for equipment located within
Division 2 or Zone 2 or 22 classified areas. METTLER TOLEDO uses intrinsically safe level c "ic"
protection method for the Analog load cell circuit and the Flow meter circuit and non-sparking "nA"
protection on other connections and the entire terminal. This means the power present is insufficient
to ignite an explosive atmosphere under normal operation conditions.
For Division 2, the protection method is non-incendive.
Other inputs and outputs to the IND780 terminal have been classified as incendive, which means
they are capable of igniting such an atmosphere if not protected. Whether an input or output is
defined as incendive or non-incendive, it must be protected accordingly. For installation in the
1-2 METTLER TOLEDO IND780 Division 2 and Zone 2/22 Installation Guide
THE IND780 TERMINAL IS NOT INTRINSICALLY SAFE FOR USE WITHIN AREAS CLASSIFIED
AS HAZARDOUS DIVISION 1 OR ZONE 0/1 BECAUSE OF COMBUSTIBLE OR EXPLOSIVE
ATMOSPHERES. FAILURE TO COMPLY WITH THIS WARNING COULD RESULT IN BODILY
HARM AND/OR PROPERTY DAMAGE.
WARNING
64063214 | 07 | 02/2018