Non-Incendive Inputs And Outputs - Mettler Toledo IND560 Serie Guia De Instalacion

IND560xx Terminal Division 2 and Zone 2/22 Installation Manual
Note that, in addition to a 25mm gland, there are three 16mm glands with a
smaller cable entry hole and two with a larger cable entry hole. Make sure to
choose the gland with the correct hole size based on the cable used. To maintain
the IP rating of the enclosure, the gland must tighten securely around the cable.
Table 2-2 lists the range of cable sizes that fit each gland.
For proper installation of a panel-mount IND560xx with an IDNet scale interface
inside an enclosure, the cable must enter the enclosure through an ATEX certified
gland. The gland must be large enough to allow the IDNet connector from the base
to pass through the center and seal around the IDNet cable. This ATEX gland is not
provided by METTLER TOLEDO.

Non-incendive Inputs and Outputs

If a specific input or output is rated non-incendive, then a list of the field circuit
parameters for that I/O will be given on the control drawing or certificate. If an
approved apparatus will be connected to a non-incendive input or output, then a
comparison must be made between the electrical field circuit parameters of both
devices including the connecting cable. These field circuit parameters include
voltage, current, capacitance and inductance. Power is not required in the
comparison of a Division 2 or Zone 2/22 application.
The two devices must compare as follows in order for the wiring to be considered
non-incendive:
C (Input capacitance) + C
i
L (Input inductance) + L
i
The field circuit parameters associated with the IND560xx terminal are underlined
in the above formulas. The other parameters are related to the other approved
apparatus or the connecting cable.
If the above conditions are not true, then the circuit must be treated as an incendive
input or output and protected accordingly. If the parameters compare favorably as
2-4
Table 2-1 : Gland Torque Specifications
Gland Size
M16
M25
Table 2-2 : Gland Cable Hole Size
Hole Size
M16 – smaller
M16 – larger
M25
U or V (Maximum voltage permitted) ≥
i max
I or I (Maximum current permitted) ≥
i max
(Cable capacitance) ≤
cable
(Cable inductance) ≤
cable
Torque
5.5 Nm (49 lbf-in)
12.0 Nm (8.9 lbf)
Cable Diameter
3 - 7 mm
6 - 10 mm
3 – 4 mm
V or U (Total voltage output)
o o
I (Total current output)
o
C or C (Allowable capacitance)
a o
L or L (Allowable inductance)
a o