Powercell Load Cell; Non-Sparking Approval - Mettler Toledo IND570xx Installationsanleitung

2.2.4.

POWERCELL Load Cell

The POWERCELL load cell connection is rated non-incendive on the cFMus approved Division 2
versions of the IND570xx terminal. The non-incendive field circuit wiring (NIFW) parameters are
listed below for the power lines, the transmit circuit and the receive circuit.
2.3.

Non-sparking Approval

The IND570xx has been approved as a non-sparking device for Division 2 and Zone 2
environments. This permits the equipment to be physically located within a Division 2 or Zone 2
area. Certain scale connections have also been evaluated as non-sparking (nA) for the ATEX and
IECEx approvals. This permits connection of a matching type of load cell in Zone 2 areas when the
load cell also has a non-sparking approval. This includes analog load cells, the IDNet High
Precision bases (using the "T-Brick T4" cell), the PBK9xx platforms (using the MPGI cell), or
POWERCELL load cells. Note that the load cell in the platform must also have a non-sparking
approval and the maximum supply voltage listed on the certificate must not be exceeded by the
IND570xx terminal.
30205321 | 05 | 03/2019
Load Cell Power
NIFW
V /u = 13.02 VDC
oc o
I /I = 304 mA
sc o
C /C = 1 µF
a o
L /L = 0.6 mH
a o
Note that there is no I or I
max
circuit will only use the amount of current required for normal operation – more current cannot
be "forced" into the receive circuit. In this case, there is no need to compare the I
as part of the NIFW calculations.
Load Cell Power
NIFW
V /u = 12.5 VDC
oc o
I /I = 1182 mA
sc o
C /C = 59.4 µF
a o
L /L = 0.2 mH
a o
NOTE: While the IND570xx with IDNet interface has been given a non-sparking approval, at
this time no METTLER TOLEDO High Precision IDNet bases are approved for use within an area
rated as Division 2 or Zone 2/22 in the United States or Canada.
METTLER TOLEDO IND570xx Division 2 and Zone 22 Installation Manual
LC Transmit (RS-422)
NIFW
V /u = 3 VDC
oc o
I /I = 250 mA
sc o
C /C = 4.4 µF
a o
L /L = 0.5 mH
a o
value listed for the RS-422 receive circuit. This is because the
i
LC Transmit (CANbus)
NIFW
V /u = 5.3 VDC
oc o
I /I = 200 mA
sc o
C /C = 1000 µF
a o
L /L = 2.0 mH
a o
LC Receive (RS-422)
NIFW
V /u = -8...+12.5 VDC
max i
- -
C = 440 pF
i
L = 0 mH
i
or I values
max i
LC Receive (CANbus)
NIFW
V /u = 26.8 VDC
max i
- -
C = 0.6 nF
i
L = 0 mH
i
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