P1.2, P1.2E
DANGER
Explosion hazard, danger of poisoning!
A crack in the bellows when conveying flammable or poison-
ous gasses may allow explosive or poisonous gas mixtures to
leak or develop.
Monitor the pump with a flow- and/or vacuum monitoring
system (see flow diagram).
If a pump defect occurs, shut it off immediately.
4.4.1.1 General monitoring measures
Since a crack in the bellow allows the ambient atmosphere to
be sucked in and the sample gas pump continues to generate
pressure, the bellows of the sample gas pumps must be in-
spected regularly.
In addition, the flow rate of the pump (to the sample gas out-
let) must be monitored with a suitable flow meter.
For more information or Inspecting the bellow the mainten-
ance schedule, please refer to the chapter Maintenance at the
end of the operating and installation instructions.
4.4.1.2 Monitoring measures when conveying
flammable and/or toxic gasses
Conveying flammable and/or toxic gasses further requires
continuous monitoring of the sample gas pump during oper-
ation. This can be done as follows (1) or (2).
1.
Flow rate monitor before the pump's gas inlet or after the
gas outlet. A sudden reduction of the suction volume /
flow volume ahead of the pump and consistent or sud-
denly increased flow volume after the pump indicates a
defective bellow (the pump can convey ambient air suc-
tioned in due to the tear).
2.
Vacuum monitoring before the pump's gas inlet and flow
monitoring after the gas outlet (see illustration). A sud-
den drop in the vacuum before the gas inlet indicates a
defective bellow.
When conveying flammable gasses above the upper explosive
limit (UEL) we further recommend monitoring the lower ex-
plosive limit (LEL) in the installation location.
When conveying toxic gasses we recommend MAC monitoring
(MAC: Maximum Workplace Concentration) at the installation
site.
underpressure
manometer
shut-off valve
sample gas pump
Fig. 1: Sample flow diagram of suitable monitoring
4.5 Electrical connections
WARNING
Hazardous electrical voltage
The device must be installed by trained staff only.
BX420021 ◦ 03/2020
Wrong mains voltage
Wrong mains voltage may damage the device.
Regard the correct mains voltage as given on the type plate.
A switch or circuit breaker (according to IEC 60947-1 and
IEC 60947-3) must be installed for the sample gas pump. It
must be easy for the operator to reach. The switch must be
marked as a cut-off for the device. It mustn't be integrated
into a supply cable or interrupt the earth conductor. It must
further separate all poles of the sample gas pump from live
parts.
Only operate the unit with the factory installed motor. The
user must not exchange the unit or replace it with a different
motor.
The sample gas pump must be protected against prohibited
heating with suitable overload protection (protective motor
switch).
Note the rated current of the circuit breaker switch (230 V =
0.48 A, 115 V = 0.84 A).
Also verify the pump motor has the correct voltage and fre-
quency (voltage tolerance ±5 % and frequency tolerance ±2 %).
The P1.2 pump (115 V/230 V) is connected to the electrical us-
ing size 6.3 mm blade terminals.
A 3 m connection cable is standard with the model P1.1E
sample gas pump.
If your sample gas pump has a factory-installed on/off switch
on the housing (only P1.2E), verify it is set to the zero position
before connecting to power.
Hazardous electrical voltage
The On/Off switch does not ensure switching off all poles.
connection. On model P1.2E the protective earth must be con-
nected to the yellow/green strands of the connecting cable
(see Fig. Electrical connections P1.2 pumps).
The supply line and earthing cross-sections must be aligned
with the rated current.
Use a minimum line cross-section of 0.75 mm
trical connection and particularly the protective earth.
Be sure to observe any varying information in the rating plate.
manometer
The conditions at the site must correspond with all rating
plate information.
Take appropriate measures to protect energised parts from
flowmeter
being touched by persons and/or interference from foreign
objects.
CAUTION
WARNING
Connect the protective earth to the motor's earth blade
2
for the elec-
Bühler Technologies GmbH
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