Discrete I/O - Solid State; Sicspro Load Cell - Mettler Toledo IND570xx Installationsanleitung

2.2.2. Discrete I/O – Solid State
The solid state discrete I/O options for the IND570xx terminal are rated non-incendive and
intrinsically safe [ic]. You cannot combine incendive and non-incendive connections or intrinsically
safe [ic] and non-intrinsically safe connections to the I/O. If any of the discrete I/O connections are
incendive or non-intrinsically safe, they must all be treated as incendive or non-intrinsically safe.
When the discrete inputs are selected as "Active" via the slide switch on the PCB, use of standard
pushbutton switches are permitted as the supply voltage is generated by the IND570 and returns to
the IND570. The signal is non-incendive and intrinsically safe [ic]. An enclosure appropriate for the
environment must be used to house the switches.
When the discrete inputs are selected as "Passive" via the slide switch on the PCB, a non-incendive
or intrinsically safe [ic] power source or an approved barrier is required to limit the applied voltage
and current. NIFW or entity values must be compared between the power source (or barrier), the
IND570xx terminal and the switch or other connected device. If the NIFW/entity values do not match
properly, then the discrete inputs must be treated as incendive or non-intrinsically safe and
protected accordingly. If switches are used, an enclosure appropriate for the environment must be
used to house the switches.
To be non-incendive or intrinsically safe [ic], the discrete outputs require the use of a non-incendive
or intrinsically safe [ic] power source or the power source must be limited by an approved barrier.
The non-incendive field circuit wiring (NIFW) and intrinsically safe [ic] entity parameters are listed
next.
2.2.3.

SICSpro Load Cell

The SICSpro 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.
2-6 METTLER TOLEDO IND570xx Division 2 and Zone 22 Installation Manual
THE ACTIVE/PASSIVE SLIDE SWITCH ON THE DISCRETE I/O OPTION BOARD MUST NEVER BE MOVED
WHILE POWER IS APPLIED TO THE IND570XX. FAILURE TO DO SO COULD RESULT IN BODILY HARM
AND/OR PROPERTY DAMAGE.
Discrete Input
(Passive)NIFW/Entity
V /U = 30 VDC
max i
I /I = 9.6 mA
max i
C = 0.01 µF
i
L = 0 mH
i
WARNING
Discrete Output
NIFW/Entity
V /U = 30 VDC
max i
I /I = 150 mA
max i
C = 200 pF
i
L = 0 mH
i
30205321 | 05 | 03/2019