Pfeiffer Vacuum ACP 28 CP, Operating Instructions Manual

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Type of gas or vapor pumped Recommended
equipment Actions/Monitoring to be
done Minimum ACP configuration ac-
cording to versions
SD G CV
Inflammable
or explosive
gas Work outside
the flammability
range of the
product (ideal =
25 to 50% of
the LEL
1 and/or
below the
MOC)
2
Connect the
gas ballast to a
neutral gas
source.
● Dilute the pumped gas
upstream or in the pump
to lower its concentration
below the lower flamma-
bility limit via purges
and/or the neutral gas
ballast.
● Dilute the gas dis-
charged by the pump to
lower its concentration to
25% of the LEL via purge
and/or the inert gas bal-
last.
● Avoid any build-up of gas
in the pumping line.
● Avoid air or humidity
backstreaming by main-
taining a gas speed
> 0.1 m/s in the exhaust
line.
● Check the sealing of the
installation.
- Purge
open Purge
open +
gas bal-
last open
1 Reference to USA NFPA 69-2002, chap. 6.3.1 Combustible concentration threshold; LEL = lower explosive limit
2 MOC Minimum Oxygen Concentration
Feature for CP - LG - SH pump versions
CP - LG - SH pump versions are designed for applications with specific qualities.
Contact our service center.
6.3 Different control modes
This chapter describes the connections and protocols associated with each control mode. 3 control
modes are available:
●
LOCAL
The pump is controlled by a switch: I/O . The pump runs independently of the equipment into
which it has been integrated.
● REMOTE
The pump is remote controlled by opening or closing different dry contacts. Its rotation speed is
configured on the terminals of the remote control connector (see chapter “Remote mode opera-
tion”.
●
SERIAL LINK
The pump is controlled by commands sent via serial link RS-485 (see chapter “Use in RS-485 link
mode”).
6.3.1 Local mode operation
In local mode, the pump can run only if the cover plug is fitted on the remote control connector. This
cover plug is delivered with the pump.
1 5 6 7 2 3 4
9 10 15 14 13 12 11
8
Fig. 6: Cover plug with strap for operation in local mode
Operation
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