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ALL DIMENSIONS mm (inches)
ALL DIMENSIONS mm (inches)
GENERAL
The unit is manufactured, checked and supplied in
accordance with our published specification, and when
installed and used in normal or prescribed
applications, with the lid in place and within the
parameters set for mechanical and electrical
performance, will not cause danger or hazard to life or
limb.
HEALTH AND SAFETY AT WORK ACT 1974
WARNINGS
1. THE USERS ATTENTION IS DRAWN TO THE
FACT THAT, WHEN THE UNIT IS "LIVE" WITH
RESPECT TO ELECTRICAL OR PRESSURE
SUPPLIES, A HAZARD MAY EXIST IF THE UNIT IS
OPENED OR DISMANTLED.
2. UNITS MUST BE SELECTED AND INSTALLED
BY SUITABLY TRAINED AND QUALIFIED
PERSONNEL IN ACCORDANCE WITH
APPROPRIATE CODES OF PRACTICE SO THAT
THE POSSIBILITY OF FAILURE RESULTING IN
INJURY OR DAMAGE CAUSED BY MISUSE OR
MIS-APPLICATION IS AVOIDED.
3. TYPE W AND A ENCLOSURES HAVE A
SAFETY BLOW-OUT DISC FITTED IN THE REAR OF
THE ENCLOSURE TO PREVENT DANGEROUS
PRESSURISATION OCCURRING IN THE EVENT OF
A SEAL FAILURE. THIS MUST NOT BE
OBSTRUCTED DURING INSTALLATION. DO NOT
REMOVE OR REPLACE WITH ANY OTHER DEVICE
NOT APPROVED BY DELTA CONTROLS.
CAUTIONS
1. Maximum single-ended or out-of balance
pressure or vacuum;
Ranges B3, B5, C2, C5 = 60 mbar
Range D5 = 100 mbar
Ranges D2, D8, F1, G0, G8 = 7 bar
All model 310 ranges are only suitable for dry gaseous
mediums. Impulse lines should be sized and installed
to avoid condensation build up affecting accuracy.
A diaphragm is used to sense the difference
between two pressures applied to either side of
the diaphragm. The diaphragm transmits a force
proportional to the applied pressure difference to
an operating beam. The beam is restrained by an
adjustable spring.
When the force on the beam overcomes the spring
tension, the beam moves and operates a switch or
switches. On reduction of the applied pressuredifference the force applied to the beam also falls,
the beam is restored to its original position by the
spring, and the switch resets.
NOTE: For accurate setting, a suitable pressure
gauge must be used in conjunction with the above
procedure. Do not attempt to set the switch outside
the scale limits. Thought the unit may be set
anywhere within its operation range, for optimum
performance, it is good practice to have a set point
value between 25% and 75% of span.
REPLACEMENT PARTS
Use only factory authorised parts and procedures.
The only parts recommended for site replacement is
the microswitch.
WARRANTIES – SEE CONDITIONS OF SALE.
NORM AL LY
OPEN
1
4
2
In the interest of development and improvement Delta Controls Ltd, reserve the right to amend without notice,
details contained in this publication. No legal liability will be accepted by Delta Controls Ltd, for any errors,
INSTALLATION, OPERATING AND
MAINTENANCE INSTRUCTIONS FOR
DIAPHRAGM ACTUATED PRESSURE
DIFFERENCE SWITCHES
SERIES 310/316
ISSUE G 07/09
PRODUCT CODE
ENCLOSURE
MODEL
ELECTRICAL ENTRY
INSTALLATION
The instruments are designed to be mounted vertically
with the process connection underneath as shown in
Figs 4 & 5, using the mounting brackets provided.
Select the mounting point so as to avoid excessive
shock, vibration or temperature fluctuation.
Instruments should be mounted to avoid excessive
heat transfer from the process line or adjacent plant.
If sudden changes of pressure (pulsations) are likely
then we recommend that snubbers are fitted between
the process line and switch.
WARNING: THE PROCESS CONNECTION
THREAD SIZE IS Rc1/4 AVOID MISMATCHING
WITH THE PROCESS CONNECTION ADAPTOR.
AVOID OVER-TIGHTENING ADAPTORS OR
DAMAGE MAY OCCUR.
WIRING (Fig 1)
Wire in accordance with local and National codes.
Use wire suitable for terminal screw and cup washer
provided on the microswitch. Deliver electrical
connection through a suitable cable gland which will
maintain the IP rating of the instrument. Keep wiring
tails to a minimum and check that wires do not
interfere with the operating mechanism. Use the
earthing points provided.
MAINTENANCE
Inspections should be carried out at quarterly to yearly
intervals depending upon operating conditions.
Isolate the unit from process and power and remove
the lid. Check all terminals for tightness. Check that
cable tails are not fouled or chafed. Check for internal
condensation. Rectify as necessary.
It is recommended that instruments used to provide an
alarm are operated periodically to ensure they are
functioning correctly.
If further maintenance is required seek advice from
DELTA CONTROLS before attempting repair or
MATERIAL OF WETTED PARTS
RANGE
SWITCHING OPTIONS
replacement of parts.
CAUTION
Moving parts have been treated with a water
repelling lubricant before leaving the factory.
Occasional inspection and the application of a
water repelling lubricant is recommended to
PROCESS CONNECTION
OPTIONS AND TREATMENTS
SPECIAL ENGINEERING
DELTA CONTROLS LIMITED, ISLAND FARM AVENUE, WEST MOLESEY, SURREY KT8 2UZ
T +44 (0) 208 939 3511 F +44 (0) 208 783 1163 E sales@delta-controls.com W www.delta-controls.com
SCREW
LOCK
SPRING
PRESSURE
DIFFERENCE
0
PRESSURE
DIFFERENCE
BAND
omissions or amendments.
YOUR TRUSTED PARTNER IN PROCESS INSTRUMENTATION
Registered Office Registered in England No 5369683
ensure moving parts remain free under all
conditions.
WARNING: DOES NOT APPLY TO OXYGEN
SERVICE.
OPERATION
Pressure difference switches are supplied calibrated
against falling pressure difference unless otherwise
specified. Set Point adjustment refers to falling
pressure difference. Switching differential is the
difference between the set point and the operating
value on rising pressure difference.
For opening details see Fig 4 and 5.
HP
FIXING
CENTRES
127 (5)
51 (2)
102 (4)
CENTRES
FIXING CENTRES
HP LP HP
51 (2)
13
(0.5)
7 (0.67)
(1.33)
142 (5.6)
102 (4)
FIXING CENTRES
51 (2)
HP
32
(1.25)
Set Point Adjustment: Models 310, 316 (Fig 2)
1. Isolate from process and power.
2. Remove the instrument lid.
3. Loosen locking plate by slackening the M3
4. Rotate the adjuster screw with a plain blade
5. Re-tighten the locking screw.
6. Replace the instrument lid (see maintenance).
PROCESS CONFIGURATIONS
For normal pressure difference operation, the
connections are made to the High Pressure (HP) and
Low Pressure (LP) ports as appropriate. For single
ended positive pressure operation the HP only is used
and the LP is left open to atmosphere.
For single ended negative pressure operation the LP
only is used and the HP is left open to atmosphere.
Use a breather/filler in the vacant port of single-ended
operation.
COMPOUND RANGES eg –2.5 to +2.5 mbar
For normal operation negative pressure is applied to
the LP port whereby the HP port is left open to
atmosphere and the set point is between 0 and +2.5
mbar.
For reverse operation, negative pressure may be
applied to the HP port whereby the LP port is left open
to atmosphere and the set point is between 0 and –2.5
mbar. For positive pressures the opposite applies.
It is recommended the minimum setting to be not less
than 5% of Full Scale (FS) either side approaching
zero (see Fig 3).
HOLES SUITABLE FOR
6 mm (0.24) DIA FIXING
SCREWS
CENTRE LINE
CONNECTIONS
Fig 4
4 MOUNTING FEET WITH
HOLES SUITABLE FOR
6 mm (0.24) DIA FIXING
SCREWS
ELECTRICAL ENTRY
CENTRE LINE
16
(0.62)
Fig 5
CONNECTIONS
Stock No: 002522/310
hexagon screw.
screwdriver to adjust the set point. Rotate
clockwise to increase the set point and counterclockwise to decrease the set point. The scale
provides an approximate set value (see note).
(0.62)
(0.8)
98 (3.85)
HP
(1.18)
(2.75)
(0.57)
30
70
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– M I C R O S W I T C H R A T I N G S
1 A @ 1 2 5 V A C R E S I S T I V E ( I E C 1 0 5 8
Low Voltage Directive (LVD) – 2006/95/AC. Switch products with enclosure codes
‘W’ and ‘A’ supplied CE-marked must be installed and used in accordance with the
main instructions and this addendum supplied with each product. Products rated
lower than 50V ac and 75 V dc are outside the scope of the LVD, and therefore, do
not require CE-marking under this directive. The LVD does not apply to products
with enclosure codes ‘H’, ‘K’, ‘R’, ‘M’, ‘N’ for use in hazardous areas. Switch products
with enclosure codes ‘H’, ‘K’, ‘R’, ‘M’, ‘N’, are covered by the Explosive Atmospheres
Directive ATEX – 94/9/EC and when CE-marked will indicate compliance with this
directive alone. The following directives do not apply to switch products
manufactured by Delta Controls:
Electromagnetic Compatibility EMC – 2004/108/EC
Machinery Safety Directive MSD – 2006/42/EC
WIRING
Cable Glands and adaptors – The enclosure is supplied with a through hole of 22 mm
blanked with a blind grommet. Discard the grommet and fit a suitable proprietary brass or
nylon M20 cable gland with thread length of 10 mm and locknut. Fit the nylon reducer
provided to the inside and a fibre washer to the outside. See diagram 1.
Alternately, the enclosure may be supplied from the factory with a threaded adaptor ready
to accept the customer’s gland or conduit system.
Alternatives:
i) a metal or nylon adaptor may be used to accommodate other sizes of gland eg
ii) an elbow kit may be supplied to enable the entry to be rotated axially through
Earthing / grounding – The user must make suitable local earthing arrangements, if
required, to ensure that metal glands are earthed.
An earthing point is provided inside the enclosure. If this is disturbed in any way it must
be reassembled correctly to be an effective earth and retain ingress protection. See
diagram 4. When removing the lid slacken the M4 nut first and ensure it is re tightened
whenever the lid is replaced. See diagram 4.1.
EARTHING / GROUNDING OF PROCESS CONNECTION AND MOUNTING
BRACKETS – All the internal dead metal work is bonded to the enclosure earthing point.
Due to requirements of sealing, the process connection and mounting brackets may be
isolated from the earthing point. Do not, therefore, rely on either for earthing, instead
always use the earthing point provided. If required, the process connection and mounting
brackets may be bonded locally. Never use the process connection or inlet pipe for
locally grounding welding equipment unless it is separately earth bonded.
Declaration of Conformity
We: Delta Controls Ltd
Island Farm Avenue
West Molesey
Surrey, UK
KT8 2UZ
As the manufacturers of the apparatus listed, declare under our sole responsibility that the products listed
below:
Pressure, Pressure Difference, Temperature & Flow switches series “W” or “A”:
201, 202, 203, 281, 204, 207, 208, 209, 231, 232, 233, 234, S21, S22, S24, GR2, GR4, VM2, VM4.
301, 303, 304, 381, 384, 306, 386, 310, 316, S31, S34, GR3, GR6.
721, 731, 771, 722, 732, 772, 723, 733, 773, 781, 734, 774, 741, 742, 743, 744, S71, GR7.
131.
To which this declaration relates are in conformity with the following relevant standards or parts thereof:
EN 60947-1 :1992 Low voltage switch gear and control-gear-general rules.
EN 60947-5-1:1992 Low voltage switch gear and control-gear-control circuit devices and switching
elements.
EN 60529: 1991 Specification for classification of degrees of protection provided by enclosures.
EN 60950:1992 Safety of information technology equipment including electrical business equipment:
section 2.5.
BS 6134:1991 Specification for pressure and vacuum switches.
And thereby conforms to the requirements of the Low Voltage Directive 73/23/EC amended by 93/68/EEC.
………………….
R. Harrison
Managing Director
Original dated 22nd June 2000
Rev. B dated 12
NPT, or conduit system. See diagram 2.
90° and radially through 360°. See diagram 3.
th
August 2009
Signed:
NUT
WASHERS
M I C R O S W I T C H
( R E S I S T I V E )
* S E E N O T E
C O D E
S W I T C H
5 A @ 1 1 0 / 2 5 0
5 A @ 1 1 0 / 2 5 0
2 A @ 3 0 V D C
1 A @ 1 2 5 V A C
* 1 0 0 m A @ 3 0
V A C
V A C
V D C
U i
U i m p
V
V
Th e electri c a l rating is d e pendent on th e microswitch f i t ted to the
instrument. T h e electrical r a t ing is defined b y each approv a l
that the mic ro s witch compl i e s with and is shown on the product
nameplate, ie UL / CSA, or IEC. It should be noted that the
switch m u s t be use d within the electr i c a l rating specified fr o m
the approval you r e quire. Table A lists the ac t ual IEC ratings
against th e Des i g n ation & Utilis a ti on Ca t e g ory ma r k e d on the
nameplate. I n the abs e n c e o f any veri f i c ation by UL / CSA the
microswitch *manufacture r ’ s ratin g is sp e c i fied in bold i t a l i cs
If in doubt, s e ek guidance f r o m factory.
Pollution degree – all products are suitable for use in pollution degree 3.
Electrical isolation – These products are not suitable for electrical isolation. Always isolate
circuit separately to carry out any electrical work.
DIAG 1
LOCKNUT
NYLON 22/20
REDUCER
DIAG 2
ADAPTOR ASSY
EARTH LABEL
COIL
WASHER
NUT
FIBRE WASHER
CABLE GLAND /
CONDUIT ADAPTOR
DIAG 4
(EXTERIOR)
BONDED SEAL
EARTHING ASSY
( I e I U e )
1 2 0 / 2 4 0 V A C
1 2 5 / 2 5 0 V D C
1 2 0 / 2 4 0 V A C
1 2 5 / 2 5 0 V D C
&
U t i l i s a t i o n
Category
C
ENCLOSURE WALL
PROPRIETARY
GLAND
CABLE GLAND ASSY
DIAG 3
FIBRE
WASHER
ELBOW ASSY
ENCLOSURE
WALL
GASKET
O RING
SEAL
SCREW
GLAND
SCREW
DIAG 4.1
M4 SINGLE
COIL WASHER
EARTH STRAP
M a k e
B r e a k
4 3 2
4 3 2
½" NPT Pg 13.5
M20 X 1.5 ¾ ET
M4 SCREW
M4 PLAIN
WASHER