BARTEC BENKE CFPP-4.2, Operating Instructions Manual

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16 Safety
CFPP Process Analyzer CFPP-4.2 03/2016
Control box and measuring cell housing
The control box (4) and the measuring cell housing (17) are pressurized (p). The housings
are connected by a flushing pipe.
By means of the key switch (3) ("bypass switch"), you can activate or deactivate the
explosion protection (overpressure monitoring) for the housings. Above the key switch
there is a label (2) explaining the key switch positions.
During normal analyzer operation (explosive atmosphere may be present), the key
switch (3) must be in position “Explosion protection ON”. The position “Explosion
protection OFF” is only intended for service tasks. In that case, you must make sure that
there is no explosive atmosphere.
The touchscreen is made of plastic. If you rub the touchscreen with a dry cloth, sparks can
occur caused by static electricity discharge. If there is an explosive atmosphere present,
this can cause an explosion. Therefore, never clean the touchscreen with a dry cloth, but
always with a damp cloth. The warning label (1) indicates this.
The control box (4) and the measuring cell housing (17) contain equipment without
individual flame protection, i.e. potential ignition sources. In addition, the housings ensure
protection against contact and foreign matter as well as protection against moisture, and
thus prevent damage to the electrical equipment. Therefore, the door (12) of the control
box and the cover (19) of the measuring cell housing must be closed during normal
analyzer operation and locked by means of the locks (10 and 16). Even after the power is
switched off, the housings may be opened only after a waiting period of 5 minutes. This is
necessary because there may be components under electric charge and with high
temperature, i.e. potential ignition sources. The waiting period allows time for electric
charges to decrease and for hot components to cool down. The warning labels (11, 18)
indicate these risks.
Junction boxes
The power supply box (7) contains the terminals for connecting the power supply,
contactors and the APEX control unit. It is required for the pressurization of the control
box and the measuring cell housing. The control unit controls and monitors the flow rate
of the protective gas and the inner box pressure during rinsing. During operation, only the
inner box pressure is monitored. During operation, the control unit activates the voltages
via the contactors.
The power supply box is open and closed using a double-bit key. Explosion protection is
provided for the power supply box by the increased safety ignition protection (e) in closed
condition only. Therefore keep the power supply box closed during normal operation.
The signal junction box (5) contains terminals for connecting the signal lines. Explosion
protection is provided for the signal junction box by the increased safety ignition
protection (e) in closed condition only. Therefore keep the cover of the signal junction box
closed with all fastening bolts during normal operation.