LEYBOLD RUVAC WH 2500, Инструкция по установке и эксплуатации

Страница: 58 / 82

Operation
58
130001398_002_C0 - 09/2016 - © Leybold
4 Operation
4.1 Start-up
Check the pump motor’s direction of rotation (see Section 3.4.6).
RUVAC WHU
The RUVAC WHU can be started together with the backing pump at atmos-
pheric pressure.
It is protected against excessively high differential pressures by a pressure
balance line.
The opening pressure of the pressure balance valve is designed only for 50
or 60 Hz operation of the pumps.
RUVAC WH
The RUVAC pumps with Leybold frequency converter are so controlled that
overloading is avoided. RUVAC pumps
without
Leybold frequency converter
need to be interlocked by means of a pressure switch so that compliance
with the values stated in the table of Section 1.3.1 is ensured.
Do not switch on the RUVAC WH until the backing pump has evacuated the
vacuum vessel down to the cut-in pressure.
For processes in which condensable vapors are pumped, it is advisable to
evacuate the vacuum vessel via a roughing line to the cut-in pressure.
Electrically switch on the Roots pump together with the backing pump and
cut it in upon reaching the cut-in pressure. The initial bypassing of the Roots
pump serves to prevent condensation of vapors in the cold pump.
Avoid flushing back of condensate because of wrong piping installation. We
strongly recommend a vertical flow direction.
NOTICE