KROHNE H250 M40 NEPSI Ex d-Ex t - Manual (Page 14)

4
ELECTRICAL CONNECTIONS
14
H250 M40
www.krohne.com 06/2013 - 4002868601 MA H250-M40-NEPSI-Ex-d-R01-
4.2 Power supply
The variable area flowmeter does not require a separate power supply. The required supply for
the built-in electronics is provided via the 4...20mA current output and the bus connection.
4.3 Inputs/outputs
The terminal assignment of the built-in electrical equipment is described in the Standard
Installation and Operation Instructions. The signal circuits of the variable-area flowmeter may
only be connected to downstream devices or circuits that satisfy the requirements of protective
extra-low voltage (PELV).
Connecting power and I/O functions
• Before connecting or disconnecting the electrical connection cables of the device, make sure
that all cables leading to the converter are isolated from the ground of the hazardous area.
This also applies to protective ground (PE) and equipotential bonding conductors (PA).
• All connecting cable conductors and shields that are not securely connected to the
equipotential grounding system of the hazardous area shall be carefully isolated from one
another and from ground (1500Vrms test voltage for non-intrinsically safe cables)
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