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Welcome to the Technical Presentation of

Shock Preventer

BY

DOLPHIN SAFETY DEVICES

EARTH LOOP VOLTAGE DETECTOR WITH CIRCUIT BREAKER

(ELVD)

• NO JOLT FROM VOLT.

• PREVENTION IS BETTER THAN CURE.

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At present

• To prevent electrical shock three wire system with protective multiple earthing is being used with rewirable / HRC fuse.

• To enhance the effectiveness of preventing electric shock to human, the installation of ELCB is recommended, even with three wire system.

• But ELCB needs effective earth to trip the power else require a secondary path for current to create unbalance in ELCB to operate and protect. Generally, the secondary path is human being or insects.

• ELCB (as per the manufacturer’s instruction) shall be tested once in month for effective protection.

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PROTECTION BY USE OF HRC FUSE

• The function of HRC or any rewirable fuse is to protect the equipment / appliances from over load and not for protecting earth leakage and shock.

• The house hold appliances like Water Heater, Washing Machine etc can be provided with glass fuse instead of HRC with cost effectiveness for overload problem.

• There is no comparison of functions between HRC fuse and ELCB / ELVD.

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NEGATIVE POINTS OF ELCB

• The ELCB is installed for an installation.• Trips power to the whole installation incase of a single defective

appliance.• Nuisance tripping in rainy season due to wet walls and poor

insulation of wires.• Needs periodical testing for full effectiveness of ELCB (as per

manufacturer of ELCB).• RCD (ELCB) does not guarantee protection against electrocution

and electrical circuits protected by it should be treated with the same respect as any other. But it does help greatly to ensure that an electrical shock is an unpleasant rather than a fatal experience (By Mathew Marks – www.inceie.org.UK – i.e. National Inspection Council for electrical installation contracting – UK and Independent Regulatory Body for Electrical Industry – UK).

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• Our ELVD (working on Earth Loop Voltage Detection principle - ELVD) with Circuit Breaker senses and isolates the faulty device so fast that you won’t have to feel that JOLT.

• “ NO JOLT FROM VOLT”.

• ELVD is far better than the conventional circuit breaker which has delayed reaction presenting hazard.

• The operating time of ELCB is < 40 milli seconds (Clause 8.7 of IS 12640-1988) where as our ELVD acts within < 10 milli seconds.

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HOW THE ELVD IS THE SAFEST WAY TO PROTECT YOUR LIFE.

• An electronic sensor in the ELVD senses and compares the voltage of the neutral and the earth terminals (Body) of the appliance.

• If the voltage level or fault signal exceeds 70 V a signal is sent to the circuit breaker to cut off power to the faulty device. All other lights and electrical devices in the home continue to function normally

• All that needs to be done to restore power to the appliance is to switch ‘ON’ the ELVD after rectifying the fault in the appliance.

Foolproof system: Until the fault in the appliances has been fixed,the ELVD will not allow the device to be powered.

Note: The sensing voltage can be set from 20 V to 100 Volts. Howeverfrom our field experience, to avoid nuisance tripping and shock, we havefixed the sensing voltage at 70 V.

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To prevent electric shock Indian Electricity Rule 1956 stipulate the following:

Rule 33:

Consumer shall in addition (i.e. other than suplier’s earthing arrangement at the consumer premises) to the earthing provided by the supplier, provide his OWN EARTHING SYSTEM with an independent electrode.

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RULE 61:

The earthing system shall have, two different earthing system through two different and separate earth electrode prepared as per the standards.

RULE 61 (5):

The earth resistance at the earth pit shall be tested once in two year for M V installation for proper and adequate earth resistance ( the value shall be less than 5 ohms).

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In practice none of the above three are never followed in domestic and L.T industrial areas. In HV industrial establishment, the records are kept to satisfy the statutory inspection.

Hence, to prevent electric shock, the ELVD, which operates even for unearthed system is Ideal for shock prevention.

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ELVD can effectively prevent electric shock to the operator and possible to avoid fire accidents caused due to electric current leakage in equipments like Air Conditioners, Motors used in a Buildings.

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If the ELVD is installed for each machine in conjunction with the MCB/CB of the main Building/Installation the maintenance of earth pit can be dispensed with or this can be considered as an added protection to human life in case of failure of earth connection, to trip the MCB.

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SPECIAL FEATURES

• Even if ground neutral loop resistance is high or open and consequent voltage rise exceeds the predetermined value between the neutral and body of appliance, the ELVD disconnects the appliances from power supply.

• Instantaneous operation i.e. Disconnects power appliance in less than 10 milli seconds.

• Designed to operate in both earthed and unearthed electrical system.

• Designed to protect both single phase and three phase appliances / machinery.

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Advantage over similar unit available in the market to prevent electric shock ItemNo.

Earth Loop Voltage Detector with Breaker (OURS)

ELCB(Earth Leakage Circuit Breaker)

1. Disconnects the defective unit alone. All other lights and power circuit will have power.

Disconnects power for the whole installation / houses as ELCB is installed for the house and not for the appliance.

2. No such necessity as power to the house will not be disturbed.

During nights when any one appliance develops defect, the whole house will be in dark. Sometimes the services of qualified technician is required to restore power.

3. Disconnects power to the defective appliances when the appliance is powered, irrespective of earth connection healthiness.

Will not operate when earth circuit in the house has high impedance or open. A secondary path with low resistance is required (usually human being / insects) to operate the device.

4. No maintenance and no testing. Periodical testing is must for the ELCB (ONCE IN 30 DAYS).

5. Operates without earth connection. Good for even two wire distribution systems.

Good earth connection is a must for proper operation.

6. No nuisance tripping of ELVD Trips due to leakage current during rainy season caused by weak insulation of wiring.

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Can be used along with ELCB and gives additional protection (as ELVD is compatible with ELCB)

EXTRACT OF CLAUSE A.02 AND A.2.4 OF IS 12640-1988

“It is Emphasized that the use of RCCB (ie.ELCB) is not considered as a sole means of Protection and it does not obviate the need to apply other protective measures”(Clause A-02).

“It is essential that an RCCB (i.e.ELCB) is not used as a sole means for protection against Direct contact” (Clause A.2.4).

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The following tests have been conducted in our factory as per IS 302-1979.

a) Protection against electric shock (clause 8.0).b) Temperature rise test as per clause 11 of IS 302.c) Dry heat test as per IS 302.d) Operating test as per product specification was conducted as below:

• Sensing Voltage• Tripping Time• Maximum current breaking capacity.

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SPECIFICATIONS

• Voltage : a) 170-250 Volts 50 Hz: b) 400-440 3 phase 50Hz

• Maximum Current breaking capacity : 20 Amps• Rating : Continuous• Power consumption : Negligible• Operating Time : <10 ms• Tripping voltage : >70 V• Type : Self Resetting

(i.e. once the fault in the load side is

cleared, the unit will allow power to the load).

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TO SAVE LIFE USE ELVD

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Electrical Accidents-Statistics

••India

•Almost 12 people die due to electrocution every day (Source -NCRB)

• 42 % of total fires occur due to electrical sources (Source -OISD)

• 8% deaths that occur in factories are due to electricity

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This product ELVD with Circuit Breaker is the patented product of DOLPHIN SAFETY DEVICE. The patent Application No.3690/CHE/2010 has been filed (under Patents Act 1970). The product was developed by the inhouse Research and Development and field tested for the last 6 years with M/s.Venus Home Appliances in their product.

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THANKING YOU

DOLPHIN SAFETY DEVICES