Pfeiffer Vacuum ACP 28 CP, Руководство по эксплуатации

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LED LED status Display Meaning
Green Off The pump is powered off.
On, constant
light The pump is powered on.
The pump has reached the selected speed.
Red Off No error
On, constant
light During pump start-up, the LED is On when the selected
speed is not reached.
Presence of an error which prevents the pump from running.
On, flashing The thermal safety indicates that the pump temperature is too
low, or too high (imminent shutdown or starting impossible).
Tbl. 4: LED meaning on a pump equipped with a three-phase frequency converter
6.5 Gas ballast operation
Principle
The user must take the appropriate measures when pumping condensable vapors or when use of the
gas ballast is required. When condensable vapors or moist air are being pumped, gas is compressed
beyond its saturated vapor pressure in the compression phase. It can condense, impairing pump per-
formance. The gas ballast can be used to inject a certain quantity of air (neutral or dry gas) into the
pump during the ‘compression’ phase so that the partial pressure of the pumped gas is less than its sa-
turated vapor pressure at the pump’s operating temperature. Condensation is therefore impossible if
this limit is not reached. The saturated vapor pressure of a body is higher when the system is hot than
when it is cold; therefore, the pump must reach operating temperature before pumping condensable va-
pors.
Using the gas ballast increases the ultimate pressure of the pump as well as the tempera-
ture.
Commissioning
To better pump with condensable vapors or moist air, the pump must be hot. Proceed as follows:
● Isolate the pump from the system (inlet isolation valve closed) and
allow it to operate for 1 hour
with the gas ballast open .
● Then, open the isolation valve: the pump operates under the best conditions by reducing the risk
of condensation inside the pump.
Recommendations
To ensure that condensable gases are correctly removed by the exhaust, we do not recommend con-
necting an ES25S.
The gas ballast function can be automated: this accessory is available upon request (see chapter “Ac-
cessories”). Likewise, the gas ballast can be supplied with filtered dry air. Contact our service center.
When there is a large amount of condensable vapor, the gas ballast is not effective enough. In this
case, using a CV version pump is recommended. Also, refer to the “Matrix gas/applications” chapter.
Gas ballast with permanent fil-
ter Gas ballast closed with a plug ON/OFF manual gas ballast
Tbl. 5: The various gas ballast models
Operation
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