IP Test or IP Code for Induction Motor

IP Test or IP Code for Induction Motor

IP means ingress protection. The degree of protection provided by the enclosure of rotating electrical machines. This protection is divided in two category:

A.      The protection provided to the person from live part, rotating parts inside the enclosure and protection of machine & enclosure to ingress of solid object.

B.      Protection provide against the harmful effect of due to ingress or dropping of water.

As we see on product specification or nameplate IP X5 or IP 55 mention. First numerical after IP is for dust (solid object) protection & the second numerical is for water or liquid protection. For example: IP X5 in this X indicates that this machine dust protection is not provided .Second digit is for water protection .Similarly  IP 55 , First numerical indicates that dust protection & second is for water protection . That means the machine is protected against dust & water both. What is that first & second numerical used in what condition or that there significance these are explain below :

1. First Characteristic Numerical: This indicates the protection gives to the person from live parts or rotating parts. The protection provide to person body, tool or rod or any wire used will not enter to the machine live or rotating part. Therefore proper clearance or distance should be maintained from rotating or live parts. To maintain this clearance protective guard is used. To confirm the clearance following  test is perform :

a.       IP 1X : 50 mm sphere test

In this test 50 mm sphere is used to confirm that the guard used to protect the live part .The holes or net on guard is not more than 50 mm.

b.      IP 2X or 6X : Finger Test

Following are the first characteristics numerical significance:

0 – Non-Protected Machine

1 – Protected against solid object greater than 50 mm

2 – Protected against solid object greater than 12 mm

3 – Protected against solid object greater than 2.5 mm

4 – Protected against solid object greater than 1 mm

5 – Dust Protected (Dust is not totally prevented but small quality of dust ingress    that will not affect the satisfactory operation of machine)

6 – Dust tight machine (Totally prevented from ingress of dust)

2. Second Characteristic Numerical: Following are the second characteristics numerical significance for IP code :

0 – Non-Protected Machine

1 – Protected against dripping water

2 – Protected against dripping water when tilted 15 ⁰C.

3 – Protected against spraying water

4 – Protected against splashing water

5 – Protected against water jets

6 – Protected against heavy seas water

7 – Protected against the effect of immersion of water

8 – Protected against effect of continuous submersion   

  

A. Test & acceptance criteria for First Characteristics Numeral :

0 – No test require

1 – Rigid sphere of 50 mm diameter is used against to apply opening of enclosure & applied force is 45 N to 55 N. If the sphere is not pass through the opening of enclosure then test is satisfactory otherwise test is fail & require modification in enclosure.

2 – A. Finger Test : For this test metallic rod or test finger is used. Joints of this finger is bent 90⁰ with respect to the axis of finger .This finger is easily push into the enclosure.  If it will not touch to their live or rotating part then test is satisfactory. To perform this test rotating part should be rotate slowly otherwise there is chance of accident.

B. Sphere Test : This test is similar to test mention in above 1. The only difference is that rigid sphere diameter used is 12.5 mm & applied force is 27 N to 33 N.

3 – Test is made with straight steel wire with diameter 2.5 mm & applied force is 2.7 N to 3.3 N. The protection of enclosure is satisfactory if the wire or rod not enter or touches to the live or rotating parts.

4 – Test is perform with use of rigid wire or rod od diameter 1.0 mm with applied force is 0.9 N to 1.1 N. Acceptance criteria is similar to mention above.

5 – A. Dust Test: To perform this test special dust chamber is require. Talcum power is used as dust in chamber. The amount of talcum powder used is 2 Kg/m³ of chamber. It will not use more than 20 test. Tested machine is put inside the chamber & pressure inside the chamber is maintained below atmospheric pressure by using vacuum pump. The test is found ok if the there is no insertion of talcum power in the object or machine.

B.  Wire Test: These test is similar to characteristics numeral 4.

6 –Test is accordance with 5A. Protection is satisfactory if there is no any insertion of talcum power.

B. Test & acceptance criteria for Second Characteristics Numeral :

0 – No test is require.

1 – The rate of the water on object or machine is uniform over the whole machine & it will produce rainfall of between 3 mm to 5 mm of water per minute. The duration of test is 10 min. The test is satisfactory if there is no any insertion of water in object or machine.

2 – Test procedure is similar to the numeral 1. The machine is tested 2.5 min. for each position. This position is 15 ⁰ either side of vertical in two manually perpendicular planes. Total duration of this test is 10 min.

3 – A. Condition 1 : The rate of water flow per hole of  tube is adjusted 0.067 to 0.074 l/min. Rate of water flow is measure by using flow meter. The tube is provided with spray holes are 60 ⁰of either side of center point & shall be fix on vertical position. This test is perform minimum 10 min.

B. Condition 2 : In this test the water pressure is adjusted to give delivery rate 10 l/min. ( Pressure approx.80 kPa to 100 kPa ). The test duration shall be 1 min/ m² of calculated surface area of machine & minimum test duration 5 min.

4 – The condition for testing is similar to numeral 3.The oscillating tube has holes drilled over whole 180 ⁰ of semicircle. The rate of water delivery & spraying time per unit area is similar to same as degree 3.

5 – The test is made of spraying the machine from all practicable direction.  The nozzle used to spraying water has internal diameter 6.3 mm. Delivery rate of water is 11.9 to 13.2 l/min.Water pressure is maintained up to 30 kPa (0.3 bar). Test duration m² of surface area machine 1 min. Minimum test duration is 3 min. Distance from machine to nozzle is approx.3 m.

6 – The test is made of spraying the water on machine by using nozzle. Nozzle internal diameter is 1.5 mm.Water delivery rate is 95-105 l/min. Water pressure at nozzle is approx.100 kPa (1bar). Test duration m² of surface area of machine 1 min. Minimum test duration is 3 min. Distance from nozzle to machine surface is approx.3m.

7 – In this test machine is completely immersing in water to satisfied following conditions:

A. Water surface shall be at least 150 mm higher than above the highest point of machine

B. Lowest portion of water shall be at least 1m below the water

C. Duration of test is at least 30 min.

D. Water temperature & machine temperature shall not be difference more than 5⁰ C.The machine is tested with inside air pressure 10 kPa ( 0.1 bar ).Duration of test is 1 Min. Test is satisfactory if there is no any air leak observe during  immersion of machine in water.

8 – Test condition is similar to the numeral 7 but they shall not be less serve than those prescribed for degree 7. This test condition is perform between the agreement of manufacturer & customer or user.

After completing the testing of the machine for first & second numeral machine Insulation measurement & High voltage test is perform on machine. To confirm that there is no any water immersion in machine .There is no any dust or water immersion in the machine or object then the test is satisfactory & machine is suitable for tested IP code. IP Test is also certification testing. Manufacture have to confirm the IP Code for the certified testing lab.