Distillation Process Analyzer DPA-4.5
Design and function
4.4.4 Junction boxes
The device is connected to the supply and signal voltages via two
separate junction boxes:
Figure 4.7: Signal junction box (1) and power
supply box (2)
The
power supply box
contains the terminals for
connecting the power supply, contactors and a control unit.
It is required for the pressurization of the control box. 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.
Ignition protection type Ex e is only ensured as long as the
power supply box is closed.
The
signal junction box
contains terminals for connecting
the signal lines.
Ignition protection type Ex e is only ensured as long as the
signal junction box is closed.
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December 2013