BEKA BA314E, Manual

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1. DESCRIPTION
These intrinsically safe, Tachometers are primarily
intended for measuring rotational speed within
hazardous areas. To assist with routine maintenance,
they also include a run-time clock that records the
number of hours that the monitored machinery has
been operating.
The BA314G and the BA314E are functionally
identical and have similar certifications, but differ in
mechanical construction and options.
The differences are summarised in the following table.
BA314G BA314E
Separate
terminal
compartment.
No Yes
Pulse output Yes Yes
Backlight Option Yes
4/20mA output. Option Yes
Dual alarms Option Yes
Certification
IECEx Gas & dust Gas
ATEX Gas & dust Gas
ETL & cETL Gas & dust Gas & dust
The main sections of this instruction manual describe
the BA314G, but also apply to the BA314E. Details of
the BA314E mounting and terminals are contained in
Appendix 4.
The BA314G and BA314E have been ATEX certified
intrinsically safe by Notified Body Intertek Testing and
Certification Ltd and comply with the European ATEX
Directive 2014/34/EU. The BA314G has gas and dust
certification, but the BA314E only has ATEX gas
certification.
The main sections of this manual describe ATEX gas
certification.
For international applications the BA314G and
BA314E also have IECEx certification which is
described in Appendix 2. The BA314E does not
have IECEx dust certification.
For applications in the USA and Canada the BA314G
and BA314E have ETL & cETL certification which is
described in Appendix 3.
2. OPERATION
Fig 1 shows a simplified block diagram of the
BA314G Tachometer. The instrument can accept
pulses from most types of sensor and display speed
per second, minute or per hour, plus run-time in
hours on a separate display.
The BA314G has a single pair of input terminals for
connection to all types of sensor. When connected to
a sensor requiring energising, such as a switch
contact, open collector or a two wire proximity
detector, an external link between terminals 3 and 4
connects power to the sensor input terminals. An
isolated pulse output can be configured to
synchronously retransmit the pulse input, or a
frequency divided frequency output with a defined
pulse width.
Factory fitted accessories include an internally
powered display backlight, dual alarms and an
isolated 4/20mA output which may be configured to
retransmit any part of the speed display.
Fig 1 BA314G block diagram
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