Operating instructions for S 40-3...S 150-3 series screw compressors
Page 25
Product description
2.5
Safety and monitoring devices
Proportional controller
(optional accessory for
S series)
The proportional controller is an additional control device intervening in the
sequences of the intake regulator.
The intake regulator only opens as far as necessary to supply the current com-
pressed air requirement. Thus the compressor saves compression energy.
A compressor with proportional controller is able to supply its ’delivered quan-
tity variable between 0% and 100%. However, the energy consumption does
not reduce accordingly. Therefore, a control is only practical between 50% and
100% of the delivered quantity.
The proportional controller is factory set to a delivered quantity between 50%
and 100% of the compressor capacity.
The proportional controller closes when the desired delivered quantity has
dropped below 50% of the compressor capacity. The compressor then oper-
ates in idling operation (continuous operation) or switches off (intermittent op-
eration).
2.5 Safety and monitoring devices
General information
The safety devices guarantee a high degree of operational safety, in connec-
tion with the BOGE monitoring system.
When one of the safety devices responds, the control system reacts as fol-
lows:
– The compressor is immediately switched off.
– A flashing fault number in the left field of the display indicates the cause of
the fault.
The following monitoring devices are standard for BOGE control systems:
Safety temperature
limiting device
The safety temperature limiting device switches the compressor off as soon as
the maximum permissible final compression temperature has been reached.
If the temperature drops below the minimum temperature, the compressor will
not start. In the event that the safety temperature limiting device intervenes in
compressor operation:
– Switch off the compressor (OFF button).
– Acknowledge fault.
– Rectify the fault.
– Switch on the compressor (ON-button).
WARNING: Risk of injury!
Do not operate the compressor without built-in safety devices!
Do not dismantle the safety devices or put them out of operation!