GAS 222.31
4.4.2 Connecting the Gas Line
Please note the following items when connecting the sample
gas line (NPT 1/4") on heated probes to prevent thermal
bridges:
• Choose the shortest possible screw connection.
• Shorten the connection pipe for the sample gas line as
much as possible. To do so, remove the insulation around
the sample gas line. This is done by loosening the fixing
bolts.
CAUTION
Fragile
The insulation is fragile. Handle with care, do not drop.
After connecting the sample gas line it must be braced and se-
cured with the clamp.
Long sample gas lines may require additional support clamps
along the way to the analysis system! Once all lines have been
connected and checked for leaks, carefully reinstall and secure
the insulation.
WARNING
Gas emanation
Sample gas can be harmful to the health!
Check the lines for leaks.
4.4.3 Connecting the calibrating gas line (optional)
Connecting the calibrating gas line requires a Ø6 mm or Ø1/4”
pipe fitting.
If the calibrating gas connection was ordered with check
valve, a Ø6 mm or Ø1/4” pipe can be connected directly to the
check valve.
4.5 Connecting the Blowback and Pressure Vessel
(Optional)
The air lines must be connected carefully and properly, using
suitable fittings.
If the probe is equipped with pressure vessel for efficient
blowback (optional), a manual shut-off valve (ball valve) must
be installed in the air supply, immediately upstream from the
pressure vessel.
NOTICE
The operating pressure of the compressed air (inert gas) re-
quired for blowback must always be higher than the process
pressure.
Required pressure differential min. 3 bar (44 psi).
DANGER
Broken pressure vessel
Gas leak, danger due to flying parts.
Maximum operating pressure of the pressure vessel 10 bar
(145 psi)!
The operating pressure reduces based on the operating
voltage (see solenoid valve type plate).
4.6 Electrical connections
WARNING
Hazardous electrical voltage
The device must be installed by trained staff only.
CAUTION
Wrong mains voltage
Wrong mains voltage may damage the device.
Regard the correct mains voltage as given on the type plate.
Electric strength test
The necessary tests of all assemblies required to be tested
were carried out at the factory (test voltage 1 kV or 1.5 kV de-
pending on component).
To check the electric strength again yourself, only do so on the
respective individual components.
• Now perform the electric strength test against earth.
4.6.1 Connection via Terminal Strip
The probe has regulated, adjustable heating. The supply
voltage is 115 V AC, 50/60Hz or 230 V AC, 50/60 Hz (see type
plate).
The device is already wired to the controller.
Inside the controller housing is a terminal block for connect-
ing the mains supply and the alarm output. The connection to
the included terminal blocks is shown in the attached connec-
tion diagram. For this purpose the plugs can be removed from
their sockets and reinserted once wired. The pin assignment is
also printed onto the board.
If the heat dissipation is very high near the probe due to the
application, the customer must install a shield to protect the
probe and regulator.
4.6.2 Heated Pressure Vessel (Optional)
A heated compressed air tank can optionally be used for blow-
back. Heated via self-regulating PTC heating cartridge to pro-
tect against frost.
If the heater was ordered with the probe, it is pre-wired.
When retrofitting with a heater, it can be powered by the
probe control unit.
Connect the connecting cable for the heater (mains connec-
tion 115/230 V AC) per the enclosed wiring diagram.
4.6.3 Heated Extension (Optional)
The unit can optionally be ordered with heated extension.
Heated via regulated heating tape with Pt100, preventing fall-
ing below the sample gas dew point at the sample point. The
unit cannot be retrofit with a heated extension.
The connection cable for the heated extension (mains connec-
tion 115 or 230 V AC) must be connected per the enclosed con-
nection diagram.
10
Bühler Technologies GmbH
BX460061 ◦ 09/2021
