ZOK-Ex
page 4 ZOK-Ex K01/0217
4. Overview
The certified ZOK-Ex series is an I.S. indicator providing a display of flowrate,
accumulated total and resettable total. It can be loop powered, battery powered
and/or dc powered via an approved associated apparatus such as an I.S. isolator.
In addition, when externally powered the certified ZOK-Ex series (not ZOK-E1)
provides one or two outputs (depending on model and configuration).
Dosing unit with one or two stage dosing using one or two opto-coupler outputs
with switching function (model ZOK-E2)
Loop Powered 4-20 mA output proportional to flow rate (model ZOK-E3/E4)
The optional alarm and/or pulse outputs must be driven each by a separate
associated device:
Low flow and high flow rate alarm (model ZOK-E5)
Scaled pulse output for remote totalisation (model ZOK-E5)
Note: ZOK-Ex electronics is not available with display backlight.
5. Mechanical Installation (also refer to ZOK-Zx series Instruction
manual)
There are additional installation requirements to the Instruction Manual for
certified ZOK-Ex series instruments in accordance with the ESHR’s as defined in
annex II of the ATEX directive 2014/34/EU.
The ambient temperature must be within the limits -20 to +60 °C.
The instruments must be installed to prevent mechanical and thermal stresses
and to prevent an attack from existing or foreseeable aggressive substances.
The instrument case is not considered to be an electrostatic risk, however
the equipment must not be installed in a position where it may be subjected
to an excessive air flow or subjected to rubbing that may cause an
electrostatic build up. In addition the instrument shall only be cleaned with
a damp cloth.
In all installations appropriate local rules, regulations and directives governing
instrument selection, installation practices and requirements must be followed.
