Delta 721 User Manual

INSTALLATION, OPERATING AND MAINTENANCE

R5.5

(0.21)

All Dimensions mm (inches)

Fig 1A

SCREW

IN D I C A T O R

M4 EARTH

120

154 (6.06)

(0.9)

Fig 7

LID L OC K M4

SO CKET CA P

14 (0.55 )

(3.3)

Fig 8

(0.47)

GLAND THREAD

ARMOURED

80 (3.14) BULB

Fig 10

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 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 MISAPPLICATION IS AVOIDED.

CAUTIONS

It is advisable to avoid the condition where the ambient temperature is within ± 5 °C of the sensed temperature, as this will increase the switching differential.

OPERATING PRINCIPLES A closed system containing an equilibrium of liquid and vapour of a suitable volatile chemical or gas is used to sense the process temperature. The pressure within the system is proportional to the applied temperature. This pressure is applied to the bellows which transmits a force, proportional to the temperature, 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 temperature the force applied to the beam also falls, the beam is restored to its original position by the spring, and the switch resets.

INSTALLATION

The instruments are designed to be mounted vertically with the thermowell connection underneath. They can be mounted either direct to process (rigid stem) or to a wall or panel using the backplate 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 lines or adjacent plant.

Capillary version

Mount the sensing bulb so that the capillary end is above the bulb and the bulb is level with, or no more than 250 mm below the base of the instrument. The bulb is fitted with a sliding compression gland to accommodate different thermowells.

When fitting the instrument lid make sure gaskets and ‘O’ rings are in good condition and fitted correctly.

CAUTION: For the rigid stem version it is recommended that a portion of flexible conduit be used to prevent undue stresses being applied to the unit. For immersion lengths refer to figs 9, 10.

WARNING: CHECK THE CONNECTION THREAD SIZE AND SPECIFICATION TO AVOID MISMATCHING WITH THE PROCESS CONNECTION ADAPTOR. SEE DIGIT 11 OF THE PRODUCT CODE.

SPDT NC=NORMALLY CLOSED COM=COMMON NO=NORMALLY OPEN

To remove lid on enclosures H, K, M loosen and rotate lid locking device (refer to fig 8). Where lid is tight use a flat bar, refer to recommended sizes below. M aterial needs to be hard chrome steel spanner grade.

The edge of a spanner may be used.

11 (.43)

(1)

LOCKING SCREW (HIGH)

SCALE PLATE (HIGH)

SCALE PLATE (LOW)

INDICATOR

2 x SPDT REAR (LO) FRONT (HI) SWITCH SWITCH

350 (13.7) MIN.

AD JUS TER KN OB

LOCKIN G SC REW LOCKIN G PLATE

SCALE PLATE

INDICATOR

FIG. 2

LOCKINGSCREW (LOW)

ADJUSTING

LOCKING SCREW (HIGH)

FRONT TOP VIEW OF SWITCHING MECHANISM

FIG. 3

INSTRUCTIONS FOR VAPOUR PRESSURE (MODELS

721, 722, 723, 731, 732, 733, 734, 781) AND GAS FILLED

FIG. 1

(MODELS 771, 772, 773, 774) SERIES 700

TEMPERATURE SWITCHES

ISSUE H 02/10

PRODUCT CODE

ENCLOSURE

MODEL

ELECTRICAL ENTRY

MATERIAL OF WETTED PARTS

RANGE

SWITCHING OPTIONS

PROCESS CONNECTION

OPTIONS AND TREATMENTS SPECIAL ENGINEERING

WIRING (Fig 1)

Wire in accordance with local and National codes. Use cables no larger than 2.5 mm2 (14AWG). Deliver electrical connection through a suitable cable gland which will maintain the IP rating of the instrument. Insert bare wires fully into the terminal block and tighten securely. Keep wiring tails to a minimum and check that wires do not interfere with the operating mechanism. Use the earthing points provided.

CERTIFIED ENCLOSURES

All Series 700 Temperature Switches can be supplied with BASEEFA certified enclosures to the following standards:

Zone 1 (Div 1) IEC 60079-0 and IEC 60079-1

CENELEC EN50 014 and EN50 018 Codes ‘H’ for aluminium and ‘K’ for cast iron II 2GD Exd IIC T6

(2.75) FIXING CRS.

7 (0.27)

Fig 6

Zone 2 (UK Only)

BS 4683: Part 3, Enclosure Code ‘N’. ExN IIT6.

174 (6.85)

(0.39)

FIXING CENTRES

ENCLOSURES W, N

ADJUST SWITCHING DIFFERENTIAL

FIG. 4

A D J U S T E R K N O B L O C K IN G P L A T E

S E C O N D A R Y A D J U S T E R K N O B

S C A L E P L A T E

S E C O N D A R Y

IN D IC A T O R

F I G . 5

2 LID RETAINING

SCREWS

ELECTRICAL

ENTRY

7 (0.27)

* FOR ENCLOSURE N ADD 10mm. (0.39)

95 (3.74)

SCREW

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,

YOUR TRUSTED PARTNER IN PROCESS INSTRUMENTATION

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

51 (2)

41 (1.61)

(0.78)

*35

All enclosures are suitable for outdoor use and the majority of products are rated IP66. Refer to the product label and / or leaflet. Only operation, maintenance or repair procedures either contained herein or approved by Delta Controls may be used, to avoid rendering the equipment unsafe in operation and / or nullifying the Certification. NO MODIFICATIONS ARE PERMITTED.

Electrical Adaptors

Zone 1. Use only certified adaptors for Zone 1. WARNING: IT IS A REQUIREMENT OF SAFETY THAT

AT LEAST 5 FULL THREADS ARE ENGAGED BETWEEN THE ADAPTOR AND CONDUIT ENTRY. TAKE CARE TO SELECT AND INSTALL ADAPTORS THAT DO NOT REDUCE THE ENCLOSURE IP RATING.

Zone 2

Adaptors used must have equivalent IP rating to the enclosure and be impact resistant to 7Nm.

References for Selection and Installation

IEC 60079-14 for Enclosure Codes H and K IEC 60079-14 for all Enclosure Codes (Intrinsic Safety) EN 50021 for Enclosure Code N IEC 50029 IP RATING (Ingress Protection)

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 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 ensure moving parts remain free under all conditions.

WARNING: DOES NOT APPLY TO OXYGEN SERVICE Zone 1 enclosures

Thread seal and contact surfaces must be lightly lubricated using a non-setting non-corrosive grease compatible with the nitrile lid seal. Do not use copper bearing grease on aluminium. Screw on lid hand tight making sure that mating surfaces of the lid and enclosure are in contact. Retighten the lid lock screw.

WARNING: IT IS A SAFETY REQUIREMENT THAT AT LEAST 5 FULL THREADS ARE ENGAGED WHEN THE UNIT IS IN OPERATION. NEVER OPERATE THE UNIT UNLESS THIS CONDITION IS MET. DO NOT USE GREASES OR LUBRICANTS NOT COMPATIBLE WITH THE ENVIRONMENT OR PROCESS.

Weatherproof Enclosure (W) and (N) If lid gasket is dried out or damaged, replace with new greased gasket.

Stainless Steel Weatherproof Enclosure (A) Check gasket. If damaged, replace.

On enclosures H, and K, remove the lid using an appropriate tool if tight, eg edge of a spanner or a metal rod (fig 1A).

(2.75) FIXING SCREW

113 (4.44)

FIXIN G

CENTR ES

(0.2 7)

(3.03)

(4.72)

(1.37)

Registered Office Registered in England No 5369683

174 (6.85)

154 (6.06)

(0.39)

FIXING

ELECTRICAL ENTRY

(0.27)

4 LID RETAINING

M4 EARTH SCREW

ENCLOSURE A

174 (6. 85)

154 (6 .06) FIXING CRS.

ELECTR ICAL

ENTRY

M5 EART H CON NECTION

SCREW

(RO TATE)

ENCLOSURES H, K, M

omissions or amendments.

SCREWS

156 (6. 14)

103 (4)

OPERATION

Temperature switches are supplied calibrated against falling temperature unless otherwise specified. Set Point adjustment refers to falling temperature. Switching differential is the difference between the set point and the operating value on rising temperature. Before commencing adjustments or removing the lid, isolate the instrument from process and power.

Set Point Adjustment: Models 721, 722, 723, 731, 732, 733, 771, 772, 773 (Fig 2)

1. Loosen the M3 hexagon head locking screw.

2. Rotate the 20 mm A/F hexagon head adjuster knob to move the indicator along the calibrated scale. Rotate clockwise to increase the set point and counter clockwise to decrease the set point.

3. Retighten the locking screw taking care not to over tighten.

4. Replace the instrument lid (see maintenance).

Set Point Adjustment: Model 781, 734, 774 (Fig 3)

The model 781, 734, 774 provides 2 microswitches which can be set independently against individual scales using a special dual beam mechanism. This fulfils the need for HI LO switching. Adjust as follows:

1. Loosen the rear M3 hexagon head locking screw.

2. Rotate the rear adjuster screw to move the indicator on the right hand (LO) calibrated scale. Rotate clockwise to increase the set point and counter clockwise to decrease the set point.

3. Retighten the locking screw.

4. Loosen the front hexagon head locking screw.

5. Rotate the front adjuster screw to move the indicator on the left hand (HI) calibrated scale. Rotate clockwise to increase the set point and counter clockwise to decrease the set point.

6. Tighten the locking screw.

7. Replace the instrument lid (see maintenance).

Switching Differential Adjustment: Model 722, 732, 772 (Fig 4)

1. Rotate the knurled plastic wheel on the microswitch to adjust the switch differential. Rotate clockwise to increase the differential and counter clockwise to reduce the differential.

2. Replace the instrument lid (see maintenance). Switching Differential Adjustment: Model 723, 733, 773

(Fig 5)

1. Rotate the secondary adjuster knob to move the secondary indicator along the ‘arrow’ scale. Rotate clockwise to increase the differential and counter clockwise to decrease the differential.

2. Replace instrument lid (see maintenance). Note: For accurate setting, a suitable temperature gauge

should be used in conjunction with the above procedure. Do not attempt to set the switch outside the scale limits. Though 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 normally recommended for site replacement are the microswitches. However, in some circumstances other spares kits are available. Apply for details quoting the serial number and full product code.

WARRANTIES – SEE CONDITIONS OF SALE

45 (1.77)

(3.03)

122 (4.8) APPROX.

(1.37)

53 (2)

39 (1.53)

196 (7.71) APPROX .

(2.79)

(0.9 8)

61 ( 2.4)

CAPILLARY

Fig 9

MODELS 721, 722, 723, 771, 772, 773, 774, 781

SENSING ELEMENT

253 (9.96)

SEMI-RIGID EXTENSION

GL AND TH READ

BULB

80 (3.14)

140 (5.5) MODEL 771-4

12 DIA

D IA.

SENSING ELEMENT

MODELS 731, 732, 733, 734

Stock No: 002522/720

WIRING

Pollution degree

TABLE A

– MICROS

WITCH RATINGS

IEC 947

-5-

1 / EN 60947

-5-

1 RATING

A C 1 4 /

2 5 0

D C 1 3 /

A C 1 4 /

D C 1 3 /

1 A @ 1 2 5 V A C R E S I S T I V E ( IE C 1 0 5 8

1 / E N 6 1 0 5 8

1 )

0 . 5 k V

D C 1 3 /

A C 1 4 /

0 . 5 k V

0 . 3 A @ 1 2 0

V A C

0 . 6 / 0 . 3 A @

A C 1 4 /

D C 1 3 /

REDUCER

‘W’ CABLE GLAND ASSY

M4 SCREW

STRAP

M4 STUD

COIL W ASHER

LID

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

ENCLOSURE ‘W’ Cable Glands and adaptors – If enclosure ‘W’ 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 NPT, or conduit system. See diagram 2. ii) an elbow kit may be supplied to enable the entry to be rotated axially through 90° and radially through 360°. See diagram 3.

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 prevent ingress. 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.

ENCLOSURE ‘A’ Cable Glands and adaptors – Enclosure ‘A’ is supplied with an M20 x 1.5 tapped hole. Use a

suitable stainless steel cable gland and sealing washer. Alternately the enclosure may be supplied with a threaded adaptor fitted at the factory ready to accept the customer’s gland or conduit system. See diagram 5.

Earthing / grounding – Bonding between the enclosure and gland / adaptor will be achieved when both parts are screwed together. 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 prevent ingress. See diagram 4.

EARTHING / GROUNDING OF PROCESS CONNECTION AND BACK PLATES – All the internal dead metal work is bonded to the enclosure earthing point. Due to requirements of sealing, the process connection and back plates 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 back plates 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

August 2009

Signed:

conditions where condensation may readily form, then sealed contacts should be used. See Table A codes 08/09, 0G/0H, H2/H3/H6.

Electrical isolation – These products are not suitable for electrical isolation. Always isolate circuit separately to carry out any electrical work.

C O D E

S W I T C H

5 A @ 1 1 0 / 2 5 0

0 0

0 1

5 A @ 1 1 0 / 2 5 0

0 2

0 3

0 4

0 5

0 8

0 9

0 G

0 H

5 A @ 1 1 0 / 2 5 0

0 C

5 A @ 1 1 0 / 2 5 0

0 D

5 A @ 1 1 0 / 2 5 0

H 2

H 3

H 6

M I C R O S W I T C H

( R E S I S T IV E )

* S E E N O T E

2 A @ 3 0 V D C

1 A @ 1 2 5 V A C

* 1 0 0 m A @ 3 0

1 1 0 / 2 5 0 V A C

5 A @ 3 0 V D C

* 1 A @ 3 0 V A C

2 A @ 3 0 V D C

– all products are suitable for use in pollution degree 3. For extreme

U L / C S A

R A T I N G

V A C

0 . 8 k V

V A C

V D C

* 5 A @

& 3 0 V D C

V A C

Uimp

0 . 8 k V

0 . 5 k V

250 V

2 5 0 V

1 2 5 V

2 5 0 V

250 V

0 . 6 / 0 . 3 A @

1 2 0 / 2 4 0 V A C

0 . 2 2 / 0 . 1 A @

1 2 5 / 2 5 0 V D C

0 . 6 / 0 . 3 A @

1 2 0 / 2 4 0 V A C

0 . 2 2 / 0 . 1 A @

1 2 5 / 2 5 0 V D C

0 . 6 / 0 . 3 A @

1 2 0 / 2 4 0 V A C

0 . 2 2 / 0 . 1 A @

1 2 5 / 2 5 0 V D C

0 . 6 / 0 . 3 A @

1 2 0 / 2 4 0 V A C

0 . 2 2 / 0 . 1 A @

1 2 5 / 2 5 0 V D C

0 . 6 / 0 . 3 A @

1 2 0 / 2 4 0 V A C

0 . 2 2 / 0 . 1 A @

1 2 5 / 2 5 0 V D C

R A T I N G

( I e I U e )

1 2 0 / 2 4 0

V A C

D e s i g n a t i o n

U t i l i s a t i o n

C a t e g o r y

D 3 0 0

R 3 0 0

D 3 0 0

R 3 0 0

A C 1 4 /

D 3 0 0

R 3 0 0

E 1 5 0

A C 1 4 /

D 3 0 0

R 3 0 0

A C 1 4 /

D 3 0 0

R 3 0 0

AC 4 3 2

D C

2 8 28

A C

4 3 2 7 2

D C

2 8 28

4 3 2 7 2

D C

2 8 28

A C

2 1 6 3 6

A C

4 3 2 7 2

A C

4 3 2 7 2

D C

2 8 28

4 3 2 7 2

D C

2 8 28

T h e e l e c t rica l r a t i n g i s d e p e n d ent o n t h e m i cro s w i t c h f i t ted t o t h e in s t r u m en t . T he e l e c t rical r a t i ng i s d efin e d b y e a c h a p pro v a l t hat t h e m i c r o s wit c h c o m p lies wi t h a n d i s s hown on t h e p r o d u ct na m e p l ate , i e U L / CS A , or I E C . I t s h o u l d b e n o ted t h a t t h e s w i t c h m u s t be u s e d w i t h i n t h e el e c t r i ca l r ati n g sp e c i f i ed f r o m t h e a p p r o v al y o u r e q u i re. T a b l e A l is t s the ac t u a l I E C r a t i ngs ag a i n s t t h e D e s ign a t i o n & U t i l i sati o n C a t e g or y m ark e d on t h e n a m epl a t e . I n t h e a b s e n ce o f a n y v e r i fic a t i o n b y UL / C S A t h e m i c r o s wit c h * m anu f a c t urer’ s r a t in g i s spec i f i e d i n b o l d ital i c s . If i n do u b t , see k g u ida n c e f rom f a c t o ry.

DIAG 1

LOCKNUT

NYLON 22/20

ENCLOSURE WALL

FIBRE WASHER

PROPRIETARY

GLAND

DIAG 2

CABLE GLAND / CONDUIT ADAPTOR

‘W’ ADAPTOR ASSY

DIAG 3

GLAND

FIBRE

SCREW

WASHER

DIAG 4.1

M4 NUT

M4 SINGL E

EARTH STRAP

ENCLOSURE

WALL

O RING SEAL

ELBOW ASSY

GASKET

½" NPT Pg 13.5 M20 X 1.5 ¾ ET

M4 PLA IN WASHE R

EARTH

BASE

EARTH LABEL

SINGLE COIL W ASHE R

NU T

PLAIN W ASHE RS

D IAG 5

NU T

STAR W ASHE R

E NCLO S U R EM 20 x 1. 5

DIAG 4

ENCLOSURE WALL (EXTERIOR )

BONDED S EA L

EAR THING ASSY

F IB R E W A S HER

A D APTO R

‘A’ AD A P T O R

Make

SCREW

Bre a k

7 2