Model 1011
Installation and Operation Manual
4
Par
t No
. 51
2083 Dra
wing No
. 1
29-0205a 03/09
Model 1011 System Accessories
Optional Enclosure Protection Vents
EPV-1-SA-00
Straight w/ spark arrestor
EPV-1-SA-90
Rt angle w/ spark arrestor
Additional Items
SMK-1, or -4
System mounting kit
EPSK-1
Class I, Group C - D pressure switch kit
EPSK-1A
Class I, Group A - D pressure switch kit
EPSK-2
Class II, Group E - G pressure switch kit
GPSK-1
Class I, general-purpose switch kit
GPSK-2
Class II, general-purpose switch kit
RAH
Div. 1 remote alarm horn
RAB-1
Div. 1 remote alarm beacon
RAB-2
Div. 2 remote alarm beacon
LCK
L fitting conduit kit
TCK
T fitting conduit kit
TR-10G
Tamperproof regulator w/ gauge
EFC-4
1/4" flush connector
EBC-4
1/4" bulkhead connector
EPC-10
1/2" pipe connector
ILF-4
1/4" filter
ETW
Enclosure temperature warning
Enclosure & Device Design
Enclosure Design Requirements
1. All windows must be shatterproof and sized as small as
possible.
2. All NFPA 496 required markings must be placed on or near
all enclosure doors and covers.
3. The enclosure must withstand an internal pressure of
ten (10) inches of water without sustaining permanent
deformation and resist all corrosive elements in the
surrounding atmosphere.
4. All lightweight objects in the enclosure, such as paper or
insulation, must be firmly secured.
5. The enclosure should be constructed from materials such as
metal or nonstatic polycarbonate to meet or exceed NEMA
4 or 12 performance requirements, but does not require
third party approval.
6. The installation of obstructions or other barriers that block
or impede the flow of protective gas must be avoided.
7. The creation of air pockets or other areas that trap
flammable gases within the enclosure or devices must be
avoided.
8. The enclosure should be located in an area where impact
hazards are minimal.
9. If the enclosure is nonmetallic and contains equipment that
utilizes or switches power loads greater than 2500 VA, it
must be constructed from substantially noncombustible
materials, such as materials designed to meet or exceed
ANSI/UL94 ratings of 94 V-0 or 94 5V.
Adjacent Enclosures
1. Adjacent enclosures must be protected by one of the
following means:
a) purged or pressurized in series with the protected
enclosure
b) purged or pressurized separately or
c) protected by other means; e.g., explosion proof
enclosures, hermetically sealed devices or intrinsic safe
circuits
2. Adjacent purged or pressurized enclosures must be
designed to meet all construction requirements above.
Total Volume Calculation
1. The total volume of all pressurized enclosures, devices and
wireways must be considered.
2. All enclosure, device, and wireway volumes must be
calculated without consideration of internally consumed
space.
Device Ventilation
1. Enclosed devices within the protected enclosure that do not
exceed 1.22 in
3
of free volume do not require ventilation to
the protected enclosure.
2. If the free volume of an internal device exceeds 1.22 in
3
it
must be protected by one of the following means:
a) ventilated on the top and bottom sides with 1 in
2
of
opening for each 400 in
3
of volume within the internal
protected enclosure, at a minimum diameter of 1/4"
b) purged in series with the protected enclosure or be
purged separately or
c) protected by other means; e.g., explosion proof
enclosures, hermetically sealed devices, or intrinsic safe
circuits.
Temperature Limitations
1. The enclosure must have no surface area that exceeds 80
percent of the flammable or ignitable substance’s auto-
ignition temperature.
2. Internal devices that exceed this temperature must be
protected by one of the following manners:
a) The device is enclosed in a chamber that is
C
UL
US
listed as a hermetically sealed device that prohibits the
entrance of a flammable or ignitable substance, and
maintains a surface temperature below temperature
limits.
b) It can be proven by testing that the devices will not ignite
the substance involved.
c) The device is purged in a separate enclosure that bears
an ETW (enclosure temperature warning nameplate).
Devices may be accessed only after power has been
removed and the device has been allowed to cool to
safe temperature, or the area is positively known to be
nonhazardous.
