HBM PX401, Руководство по эксплуатации

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Electrical connections PMX
70
A4354-2.2 HBM: public
PMX
8.4 Measurement cards / transducer
connection
8.4.1 Intrinsically safe measurement circuits -
Operation with Zener barriers
To operate transducers (load cells, force transducers,
etc.) in potentially explosive atmospheres, intrinsically
safe measurement circuits (Ex II (1) GD, [EEx ia]IIC)
must be set up on the PX455 by connecting safety
barriers (Zener barriers) type SD01A. The safety barriers
must also be mounted on the DIN rail like the PMX. An
ATEX test certificate must be available for the
transducers used. Transducers with 350 ohm bridge
resistance can be used. One transducer per
measurement channel of the PC455 can be operated
(parallel connection is not possible).
The PX455 offers 4 measurement channels with 4.8kHz
carrier frequency measurement. If the measurement
signals need to be added/subtracted or mean values
formed, this can be set using the internal PMX calculation
channels.
Important
In addition to the SD01A, the negative operating voltage
of the PMX must be grounded!
Cable lengths of up to max. 100 m are permissible. TEDS
cannot be used.
The measurement accuracy of the PX455 with operation
of the SD01A is max. 0.5%.