Commissioning, operation – WIKA TR31 Benutzerhandbuch
Seite 18

GB
14096788.01 07/2014 GB/D
18
WIKA operating instructions models TR31-3, TR31-K
6. Commissioning, operation
WARNING!
Avoid putting any mechanical loading on the electrical
connections and on the enclosures. Connections must only
be opened once the instrument has been depressurised and
has cooled down.
Maximum permissible temperatures:
■
Without neck tube: -50 … +150 °C (-58 ... +302 °F)
■
With neck tube: -50 … +250 °C (-58 ... +482 °F)
1)
■
At case with transmitter: 85 °C (185 °F)
■
With directly connected cable: -20 ... +80 °C (-4 ... +176 °F)
1) Version with mineral-insulated sheathed cable can be used up to 300 °C (572 °F).
6.1 Mounting
These resistance thermometers are designed for screw-fitting directly
into the process. The insertion length, along with the flow velocity and
viscosity of the process media, may reduce the max. loading on the
thermowell.
The housing must be grounded against electromagnetic fields and
electrostatic discharge. It is not necessary to connect the housing
separately to the equipotential bonding system, provided that it has a
fixed and secure contact to the metallic vessel, its components or pipes,
and that these are connected to the equipotential bonding system.
When there is a non-metallic contact with the vessel, or with its
structural components or piping, the instrument must be provided with
equipotential bonding.
WARNING!
Neither repairs nor structural modifications are permitted,
and any would void the guarantee.
6. Commissioning, operation