Advanced SG6540 User manual

INSTRUCTIONS
FOR MODELS SG6540 & SG6541
PRESSURE SWITCHES
THIS BOOKLET CONTAINS PROPRIETARY INFORMATION OF
ADVANCED SPECIALTY GAS EQUIPMENT CORP. AND IS PROVIDED
TO THE PURCHASER SOLELY FOR USE IN CONJUNCTION WITH
MODELS SG6540 & SG6541 PRESSURE SWITCHES.
IMPORTANT
These instructions are for experienced operators who know the
general principles and safety precautions to be observed in electrical
wiring and handling specialty gases. If you are not certain you fully
understand the safety precautions for handling gases, we urge you
to obtain and read the Material Safety Data Sheet (MSDS) for each
gas being used.
Do not permit untrained persons to install, operate, or maintain these
pressure switches. Do not attempt to install or operate this pressure
switch until you have read and fully understand these instructions.
If you do not fully understand these instructions, contact your
Advanced Specialty Gas Equipment Distributor.
Be sure this information reaches the operator. Your supplier has
extra copies.
ADVANCED
Specialty Gas Equipment
Model SG6540

SAFETY PRECAUTIONS
Protect yourself and others. Read and understand the following
instructions before attempting to use these pressure switches. Failure
to understand and follow these instructions could result in serious
personal injury and/or damage to equipment.
•Know and understand the physical and chemical properties of
the gas being used.
•Wiring must comply with Local and National Electric Codes.
•Observe safety precautions for the gas being used.
•Read and follow precautions on cylinder labels.
•Never use these pressure switches with gases not compatible with
the materials of construction. The use of gases not compatible with
the materials of construction may cause damage to equipment or
injury to personnel.
•If flammable gases are used with these pressure switches, use
Explosion-Proof Model SG6541.
•We recommend the use of the Explosion-Proof Model SG6541 for
Oxygen Applications. This model contains a hermetically sealed
switching element, which provides a safe environment for handling
pure oxygen.
•If toxic or flammable gases are used with these pressure switches,
emergency equipment applicable to the gases in use should be
available in the operating area.
•Many gases can cause asphyxiation by displacing oxygen in the
atmosphere. Make certain the area where pressure switches are
connected is well ventilated. Provide a device to warn personnel of
oxygen depletion in the work area.
•Electrical rating must be within range stated on the switch name
plate (see page 7). Failure to stay within the rating of the switch may
result in damage to, or premature failure of, the electrical contacts.
•Disconnect electrical power supply to switch before removal
or inspection.
•Relief devices should be installed and properly vented in all gas
handling systems to protect against overpressurization.
•Never use oil or grease on these switches. Oil and grease are easily
ignited and may combine violently with some gases under pressure.
•Never connect a pressure switch to a supply source having a
pressure greater than the maximum rated pressure of the pressure
switch. Refer to Product Specifications (see page 7) for maximum
inlet pressures.
2

MANUFACTURER STATEMENT
The information contained in this instruction booklet has been
compiled by Advanced Specialty Gas Equipment Corp., (the
Company), from what it believes are authoritative sources and is
offered solely as a convenience to its customers. While the Company
believes that this information is accurate and factual as of the date
printed, the information including design specifications is subject
to change without prior notice.
DESCRIPTION
The Models SG6540 and SG6541 pressure switches are designed to
monitor line pressure and activate an external alarm (not supplied)
when a certain predetermined pressure is reached. They can be set to
activate on either increasing or decreasing pressure.
The pressure sensing element of the pressure switch is a force-balance,
piston-actuated assembly, sealed by a flexible Stainless Steel
diaphragm and a static O-Ring. There are three wetted parts to the
pressure switch: a pressure port, a diaphragm and an O-Ring seal
(Fig.2 see pg.9). Media pressure on the piston counteracts the force of
the range spring (adjustable by the set point adjusting nut) which
moves the piston shaft only a few thousandths of an inch to directly
actuate the switching element.
Model SG6540 is a general service pressure switch for use with non-
flammable gases. The explosion-proof Model SG6541 is UL listed and
CSA certified for use in hazardous locations; Class I group A, B, C, D
and Class II group E, F, G. Each model has a single-pole, double
throw, electrical switch with a maximum rating of 15 amps at
250 VAC. Their NEMA 4X weathertight housings are constructed
of aluminum.
Each pressure switch is supplied with two compression-type male
connectors and five feet of 1⁄8in. OD stainless steel tubing for connec-
tion to a manifold or pipeline.
3

MOUNTING
WARNING: Before attempting to install and operate these pres-
sure switches, read and fully understand the safety precautions
on page 2 in this booklet. Failure to follow the safety precautions
may result in serious personal injury and/or damage to equipment.
1. Pressure switches are usually mounted adjacent to the end of the
manifold and connected to the manifold header with 1⁄8inch tubing
and compression-type male connectors supplied with each unit.
2. The device can be mounted in any position however, for weather
tight installation in high humidity areas, orient housing so electri-
cal connection is at the 6 o’clock position to prevent condensate
from collecting in the housing enclosure.
Note: Line mounting by either process connection or electrical
connection is not recommended.
3. Secure housing mounting pad to the wall or other support with
two suitable 1⁄4inch bolts.
Note: When mounting to irregular or uneven surface, install rub-
ber washers (provided) on bolts between housing and mounting
surface to prevent deformation of housing, which could change
relative positions of internal parts and affect calibration or render
the device inoperative.
PROCESS CONNECTION
WARNING: DO NOT exceed pressure and temperature specifica-
tions during operation. DO NOT operate the pressure switch
under any circumstances if it leaking or otherwise malfunction-
ing. Damage to equipment and/or injury to personnel may result.
1. Connect 1⁄4in. NPT male x 1⁄8compression connector to pressure
switch using two wrenches: one to hold hex flats on pressure port,
the other to tighten male connector. Use Teflon®tape on all pipe
threads to prevent galling.
Note: Be certain process connection is tightened and positioned so
bending and torsional forces imposed on pressure switch are mini-
mal. Use care not to loosen pressure port from body or body from
housing.
2. Connect 1⁄8in. NPT male x 1⁄8compression connector to manifold or
pipeline.
3. Install 1⁄8 in. tubing between pressure switch and manifold or pipe-
line using the male connectors installed in steps 1 and 2 above.
4. Leak test all connections with a nonhazardous gas using either a
soap solution, such as Snoop®or a gas leak detector.
4

ELECTRICAL CONNECTION
WARNING: Electrical power must be disconnected prior to con-
necting wiring to pressure switch. Damage to equipment and/or
injury to personnel may result.
Each model has a single-pole, double throw, electrical switch with a
maximum rating of 15 amps at 250 VAC. For decreasing pressure
activation use the normally closed (NC) contact. For increasing pres-
sure activation the normally open (NO) contact must be connected.
Note: Storing excess wire or making wire lead splices inside the pres-
sure switch housing will interfere with pressure switch operation.
General Service Switches
Electrical connections are made to the three screw-type terminals
inside the housing with wiring access through a 3⁄4 in. NPT female
conduit connection (Fig.3 see pg.9). The three switch terminals
are clearly marked: normally open (NO), normally closed (NC)
and common (C).
Explosion-Proof Switches
Electrical connections are free leads; 18 gauge, 18 in. with ground
wire and 3⁄4in. NPT female conduit connection (Fig.4 see pg.10).
The wiring is clearly marked: Black-normally opened (NO), Red-
normally closed (NC), Blue-common (C) and Green-ground (GND)
(Fig. 1 below).
Note: The hermetically sealed, explosion-proof switching element
capsule located within the pressure switch housing, has UL Listed/CSA
Certified factory-sealed leads. Consequently, an external seal fitting
is not required between the pressure switch and junction box of the
external electrical circuit.
5
Wire Lead Color Code
SPDT
Blue (C)
Black (NO)
Red (NC)
Green (GND)
Pressure
Figure 1 – Model SG6541 Wiring Diagram Schematic

CALIBRATION
The switch is factory-set to operate at the pressure specified by the
purchaser. It may, however, be adjusted within its adjustable range.
Refer to Product Specifications (see page 7) for adjustable ranges.
WARNING: Electrical power must be disconnected prior to chang-
ing pressure settings. Damage to equipment and/or injury to per-
sonnel may result.
1. To change the pressure switch set point, remove the weathertight
cover from the housing.
2. Use a 3⁄4in. open-end wrench to turn hex adjusting nut clockwise to
increase set point; counterclockwise to decrease set point.
Approximate set point can be obtained by sighting across top of
adjusting nut to calibration scale on interior wall of housing.
Note: If precise set point is required, it will be necessary to use a
regulated pressure source, a suitable continuity tester and a 1⁄4%
test gauge.
3. Replace housing cover and gasket to ensure weathertightness.
MAINTENANCE AND REPAIRS
Pressure switches do not normally require periodic service. If a pres-
sure switch leaks or malfunctions, take it out of service immediately.
Do not attempt to repair, modify or changeout wetted parts. Repairs
or modifications should be made by Advanced Specialty Gas
Equipment Corp. who have the special tools, test equipment and
trained personnel required to make a safe repair. Contact your
Advanced Specialty Gas Equipment Distributor to arrange for repair.
Warranty Repairs are only available through Advanced Specialty Gas
Equipment Corp., and will be performed at no charge for parts and
labor. For information on warranty, see the last page of this instruc-
tion booklet.
Non-Warranty Repairs are available through your distributor. Upon
receipt at the factory, the pressure switch will be inspected and you
will be contacted by your distributor with a repair cost estimate. No
item will be repaired until approval is received. There will be an eval-
uation charge assessed for equipment not repaired.
6

SPECIFICATIONS
Maximum Operating Pressure See Table 1
Operating Temperature Range -30°F to +200°F (+32°F to +400°F
with Viton®seals)
Adjustable Pressure Range See Table 1
Electrical Rating 15 amps at 250 VAC (max.)
Minimum Current Required 100mA
DC Rating (resistive loads) Low Level (30 volts) - 5 amps
High Level (125 volts) - 0.4 amp
Housing NEMA 4, 4X, 1P65
Pressure Port Connection 1⁄4in. NPT female
Male Connectors (2 supplied) 1⁄4in. NPT male by 1⁄8in.
compression
1⁄8in. NPT male by 1⁄8in.
compression.
Tubing 5 ft. x 1⁄8in. O.D.
Weight (approx.) 2 lb. (Model SG6540)
3 lb. (Model SG6541)
7

MATERIALS OF CONSTRUCTION
Housing Aluminum
Diaphragm Type 316 Stainless Steel
Pressure Port Type 316 Stainless Steel
Seals See Table 1
Male Connectors Type 316 Stainless Steel
Tubing Type 316 Stainless Steel
Table 1
Max.
General Explosion- Inlet Adjustable O-Ring
Service Proof Service Pressure Range* Seal
Part Number Part Number (psig) (psig) Material
SG6540-2-N-(*) SG6541-2-N-(*) 3000 12–100 Neoprene
SG6540-2-V-(*) SG6541-2-V-(*) 3000 12–100 Viton®
SG6540-3-N-(*) SG6541-3-N-(*) 3000 45–550 Neoprene
SG6540-3-V-(*) SG6541-3-V-(*) 3000 45–550 Viton®
SG6540-4-N-(*) SG6541-4-N-(*) 5000 500–4000 Neoprene
SG6540-4-V-(*) SG6541-4-V-(*) 5000 500–4000 Viton®
Note: Where “(*)” is indicated above, insert desired pressure setting.
Example: SG6540–2-N-20. Switch will be factory set to activate
at 20 psig.
Models SG6540-4 and SG6541-4 can be factory set to activate up
to 2000 psig. Settings for pressures above 2000 must be field set.
*Other ranges available on special order.
8

9
11/8"
(28.6mm)
SIDE VIEW
115/16"
(49.3mm)
FRONT VIEW
4"
(101.6mm)
23/4"
(69.9mm)
15/16"
(33.3mm)
21
/8"
(54.0mm)
3"
(76.2mm)
511
/16"
(144.5mm)
33/8"
(85.9mm)
21 /8"
(54.0mm)
Conduit Connection 3/4" NPT Female
25/32"
(19.8mm)
Pressure Port
1
/4" NPT Female
Figure 3 – SG6540 General Service Pressure Switch
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Switching
Element
Set Point
Adjusting Nut
Pressure Range
Spring
Diaphragm*
O-Ring Seal*
Pressure
Port*
Calibration
Scale
Housing
*Wetted Parts
Piston
Assembly
Figure 2 – Model SG6540 Internal View

10
BOTTOM VIEW
43/4"
(120.7mm)
23/16"
(55.6mm)
51 /4"
(133.4mm)
41 /4"
(108mm)
33/16"
(81.0mm)
11 /2"
(38.1mm)
21
/8"
(54.0mm)
FRONT VIEW
TOP VIEW
Conduit Connection
3/4" NPT Female
1
/4" Dia. Thru
(Typical)
Pressure Port
1
/4" NPT Female
Figure 4 – SG6541 Explosion-Proof Pressure Switch

WARRANTY
Advanced Specialty Gas Equipment Corp.,(the Company), warrants
to the initial purchaser of each pressure switch described herein, that
such equipment will be free from defects in material and workman-
ship which result in breakdown or failure under normal use during a
period of 12 months from date of shipment by the Company if used
and maintained according to Advanced Specialty Gas Equipment
written instructions. This warranty does not cover damage or mal-
function due to corrosion. Purchaser is aware that this equipment is
designed for specific applications and that using this equipment with
the wrong or improperly purged gas or at the wrong pressure may
damage or corrode the unit and cause personal injury. Purchaser
must confirm that this equipment is compatible with the gas being
passed through it. If there is any doubt about compatibility, consult
your Advanced Specialty Gas Equipment Corp. distributor.
The Company’s liability under this warranty shall be limited to the
repair, or at its option, replacement or refund of the purchase price,
of such equipment which proves to be defective, provided; however,
that this warranty shall only apply if the purchaser (1) gives the
Company written notice within ten (10) days after discovery of such
defect, (2) immediately on discovery of the claimed defect, discontinues
all use of such equipment, and (3) returns such equipment freight
prepaid to plant of manufacture.
THERE ARE NO EXPRESS WARRANTIES OTHER THAN THOSE
SPECIFIED HEREIN. NO WARRANTIES BY ADVANCED SPECIALTY
GAS EQUIPMENT CORP.(OTHER THAN WARRANTY OF TITLE
AS PROVIDED IN THE UNIFORM COMMERCIAL CODE) SHALL
BE IMPLIED OR OTHERWISE CREATED UNDER ANY APPLICA-
BLE LAW, INCLUDING BUT NOT LIMITED TO WARRANTY OF
MERCHANTABILITY AND WARRANTY OF FITNESS FOR A PAR-
TICULAR PURPOSE. No claim against the Company of any kind,
whether as to equipment delivery or for nondelivery of equipment
and whether or not based on contract, warranty, negligence, strict
liability in tort or otherwise, shall be greater in amount than the pur-
chase price of the equipment in respect of which such claim is made.
Without limiting the generality of the foregoing, Advanced Specialty
Gas Equipment Corp. shall not be liable for any special, indirect, or
consequential damage, such as failure of parts resulting from corrosion.
If it is determined by Advanced Specialty Gas Equipment Corp. that
the equipment is to be repaired or replaced under the terms of this
warranty, the cost of returning said equipment to the initial purchaser
will be paid by the Company. If, however, equipment returned to the
Company in connection with a claim under this warranty is found
by the Company not to be defective hereunder, then such equipment
will be returned to the initial purchaser, shipping charges collect, and
additionally, a service charge will be paid by the purchaser to the
Company to cover the cost of handling and testing such equipment.
11

Printed In U.S.A. AI 2030R
Copyright ©1999 Advanced Specialty Gas Equipment Corporation 8/99
Snoop is a registered trademark of Nupro Co.
Teflon and Viton are registered trademarks of E.I. Du Pont de Nemours & Co.
Specialty Gas Equipment
ADVANCED
241 Lackland Drive, Middlesex, NJ 08846
Phone: [phone] Fax: [phone] www.asge-online.com