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8
Instruction Manual category 2G handheld unit flowtherm Ex
Non-compliance can cause an explosion!
8.1
Apparatus
Handheld unit flowtherm Ex for connecting vane wheel flow sensors FA in the design of probe and measur-
ing tube, vortex flow sensors VA in the design of VA40 probe and measuring tube VA Di, thermal flow sen-
sors TA in the design of TA10 probe and measuring tube TADi, as well as temperature sensors Pt100. Fur-
thermore the handheld unit has a 4 ... 20 mA and a 0 ... 10 V analog input for connection of other suita-
ble, also manufacturer-independent sensors.
Intended use
The handheld unit flowtherm Ex with the above mentioned sensors for use in explosive atmospheres cate-
gory 2G is for measuring flow velocity, flow rate and temperature of gases, with vane wheel sensors FA
and Pt100 sensors specified for this purpose also in liquids. They are designed for use in area in which
category 2G apparatus is required.
During operation the maximum admissible values for current, voltage, power, internal and external in-
ductances and capacities are limited. Furthermore the maximum admissible surface and component tem-
perature is limited.
Handheld unit flowtherm Ex with corresponding sensors must not be used
in areas in which category 1G or 1/2G apparatus are required and
in areas in which category 1D, category 2D or category 3D apparatus are required
8.2
Safety Precautions
8.2.1
General
Hazard risks:
- modifications to the device by the customer
- handling the devices outside the specified operating conditions
- handling the sensors outside the specified operating conditions
- improper use of the device
Danger when installing the sensors in pressurized pipelines:
-
sensors for use in pressurized pipelines sensors are to be inserted or retracted only in depressurized
conditions; non-observance may result in serious harm to personnel
-
when installing or removing under pressure, the appropriate protective equipment must be used, e.g.
ball valve and probe guide pieces with chain guard or spindle probe guide pieces
The medium container for the measuring gases must be insulated in a way that is it ensured that the elec-
tronics housing of the apparatus does not assume a higher temperature than the aforementioned maxi-
mum ambient temperature; radiation and convection heat has to be considered also.
8.2.2
Use in explosive atmospheres
Danger when using in explosive atmospheres:
-
the device and its sensors may only be used in areas specified for category 2G (zone 1) apparatus.
-
If sensors with category 1/2G or 1G markings are connected to the device they may be used in catego-
ry 2G only! (See corresponding sections of Instruction Manual of the sensors and the declaration of
conformity)
-
When using extension cables, the corresponding products of Höntzsch may only be used. Make sure
that they are tightly screwed and that they may only be connected and separated outside the explosive
atmosphere.
