Flow Rate Curves - Pepperl+Fuchs 7500 User Manual

Mass
Dimensions
Mounting
Data for application in connection with hazardous areas
Certificate
Marking
International approvals
cULus
IECEx approval
2.4.2

Flow rate Curves

The enclosure pressure vs. flow rate curves below represent the EPV-7500....-01, 02,
03, and 04 vents. This corresponds to the enclosure pressure and is independent of
the valve used, provided the valve can deliver the flow rate that is required.
The vent flow tables represent the flow rate and enclosure pressure for each vent
with a safety margin attached to the values. Enclosure pressure may be less than the
tables below for actual measured value. The values below do not take into account
leakage from the enclosure; they represent a perfectly sealed enclosure. In most
applications, the enclosure will have leakage, which will require higher flow rate
into the enclosure to achieve the correct reading. This extra flow will depend on the
leakage throughout the enclosure.
There is no restriction of enclosure size for each vent, but leakage rate, flow rate,
enclosure pressure, and the 7500 maximum purge time of 254:59 (min:sec) should
be considered when applying these vents.
The EPV-7500-...-01 is usually used on large enclosures because it has a higher flow
rate and lower back pressure within the enclosure than the other versions. This can
reduce the purging time while keeping the enclosure pressure low, which is important
for a large enclosure. However, this vent leaks more pressure through its flow control
mechanism.
The EPV-7500-...-02 provides a better seal at the vent than the EPV-7500-...-01. The
flow rate for purging is less for the same enclosure pressure of the '-01' version.
The EPV-7500-...03 features a flow rate that is less than both the '-01' and '-02'
versions, and provides very low leakage, which is recommended for very small
enclosures.
approx. 1000 g (2.2 lb)
See dimensions in Section 2.4.3 Dimensions: EPV-7500 Vents
EPV-7500-...-01/02/03: 1½ in NPMS thread; mounting hole 50.8
mm (2 in) sealing washer and nut (provided)
EPV-7500-...-04: M36 thread; mounting hole 37 mm (1.46 in) with
sealing washer and nut (provided)
ATEX: part of 18ATEX2025X
Part of the cULus classified 7500 purge system
Part of IECEx UL 18.0022X
7500 S M  P
erieS anual
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roducT eScriPTion
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