OIL LEVEL INDICATORType SO-4 & SO-6

(Magnetic)

FEATURESFEATURES

IN SERVICE TO THE TRANSFORMER INDUSTRY SINCE 1971

Aluminium (LM6) Die-cast body and components.Housing treated against Porosity through a special process.Complete meshing of teeth to avoid play in the gears.No overshooting of the pointer on the dial at the two extremes possible.The cam assembly can be pre-adjusted as per customer’s requirement to set off the alarm at any point before theempty position.Precision positioning of magnets to ensure complete union in their movement.The presence of only one box at the bottom of the dial offers simplicity in design & avoids excess internal wiring in theindicator

AT-201

1. MERCURY SWITCH2. INTERNAL WIRING3. CONNECTOR4. EXTERNAL WIRING5. ALARM

MERCURY SWITCH CONTACT RATINGAC 240V 5 Amp.DC 240V 0.5 Amp.

Note: This design permits operation of switch nearLow Level only.

FIG. 1

FIG. 2

WIRING DIAGRAM

PARTS LIST

SR. No. DESCRIPTION MATERIAL

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

MAIN BODY

LIMIT STOPPERS

LEVER WITH GEAR

FLOAT-ARM

FLOAT

HOLE FOR CABLE GLAND

CONNECTOR

MERCURY SWITCH GLASS

NUT (FOR ADJ. MER. SWITCH)

DIAL WITH POINTER

AL (LM6)

BRASS

BRASS

BRASS

BRASS

GLASS

BRASS

AL

ALL DIMENSIONS IN mm

300

1/4

1/2

3/4

EMPTY FULL

MADE IN INDIA

9 8 6 7 10

SUPPLY 1

2

3

4

5

3/4” B.S.Conduit orMetric on demand

1

2

3

4

5

MODEL

DIAL SIZE

A

B.Ø

C

D

E

F

GØ

H (Nos)

P.C.D.

Weightin Kgs.

SO-4

100

184

125

48

12

65

50

11

6

165

2.5

SO-6

150

230

186

48

12

65

50

13

8

209.7

3.0

CONSTRUCTION & WORKING

CALIBRATION

ALARM SWITCH

APPLICATION

The ‘ATVUS’ Magnetic oil Level Gauge consists of the mainbody, with the following sub-assembly / parts :1. Gear assembly2.Magnetic couple3. Float with arm4. Cam assembly withMercury Switch5. Dial with pointer

The schematic diagram of the full assembly is shown below.

The float is hinged and swings up or down when Oil Levelrises or falls. This rise or fall rotates the bevel gear and thusthe pinion of the gear assembly. The pinion in turn rotates thedriving magnet inside the conservator. The follower magnetpositioned outside carries a pointer and a cam. The pointerreads Oil level and the cam is set to operate the mercuryswitch at a predetermined low level.

MOUNTING

A suitable pad has to be provided to mount the indicator. Themounting can be done vertically or at an inclination to facilitate

easy viewing. The different mounting positions are illustratedin fig. 5.

The dial is calibrated as per customers specifications. Hencea drawing showing heights of oil levels inside the conservatorat corresponding marking on dial should be made available.Generally a minimum distance of 60 mm should be leftbeyond the two limit makings i.e. Empty & Full. Calibration isalso possible in other units.

One, normally open, mercury switch is provided to actuatelow level alarm. The switch is adjustable to compensate errorin orientation of pad. Leads of this switch are connected tothe terminals.

The ‘ATVUS’ Magnetic Oil Level Gauges can be used forvarious purposes. In a transformer they are mounted on theconservator to read oil level and to set off an alarm when theoil Level falls below a predetermined level.

FIG. 3

1. Operating liquids2. Working temperature3. Working Pressure4. Environment5. Electric Switch6. Contact Rating7. Switch Operation

8. Weight & Dimensions

: Transformer oil to IS 335 and other oils.: 0 to 100 C of oil.: 0 to 4 Kg/cm: Suitable for indoor and outdoor use.: One SPST Mercury Switch.: 5 Amps 240V AC. 0.5 Amp 240V DC.: Normally open, closes when oil level drops to near empty condition.

Switch recovers automatically on rising of oil level.: See table 1 in fig. 1.

o

2

SCHEMATIC

Dial

Driven Magnet

Metallic Wall

Driving Magnet

Cam

Pointer

Mercury Switch

Gear and Pinion

Float

IN AIR IN LIQUID

SPECIFICATIONS

INDUSTRIES689, Block ‘O’, New Alipore, Kolkata - 700 053, INDIA

Phones: (91-33) 24001101, 24009885 Fax: (91-33) 24007443, 24007043 E-mail: atvus@dataone.in

1) Indicators with different specifications are not interchangeable.

2) Indicators suitable for synthetic Liquid are available.

3) Calibration of dial in other units is possible.

The following should be specified while ordering.1. Mounting position of indicator.2. Dial Marking.3. Conservator Dia.4. Air cell in conservator (if any).5. Oil level inside conservator, corresponding to dial marking.Note: 1) Leave minimum 60mm beyond limit of marking to avoid

striking of float to conservator wall.2) A separate Questionnaire is made available in which

details of technical specifications required by us are given.Please ask for the same.

Due to our policy of continuous product improvement, dimensions and designs are subject to change.

DETAILS OF MOUNTING PADS

APPLICATIONS

1. Indicator mounted centrallyon flat wall of conservator.

2. Indicator mounted at aninclination for easy viewing.

3. Indicator mounted on air-cell typeconservator.

Conservator

Air-cell

Float

MOG

Note: Indicators can be mounted in other positions also. However, we have illustrated only three applications.

FIG. 4

Model SO-4

6 STUDSM 10 ON 165 PCDA=31 B=120C=130 D=190

8 STUDSM 10 ON 209.7 PCDA=31 B=165C=175 D=236

Model SO-6

FIG. 5

GENERAL NOTES HOW TO ORDER

Note:1. The mounting pad is not in

our scope of supply. Hence onlyimportant dimensions are shown.

2. Pad should be welded to conservatorwall with correct orientation.

3. Use gasket of 4 to 6 mm thickness.