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Dave Nova
Dave Nova, ASE Certified Tech
Category: Car
Satisfied Customers: 19452
Experience:  ASE Master Certification. GM World Class Certification
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I am in the market to buy a Jump starter but have no clue about how it

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Hi, I am in the market to buy a Jump starter but have no clue about how it works. So here are my questions

1. What are the things I should look for in a Jump Starter, like specifications and why?
2. I looked in the market and some articles are saying I have to look for CCA and CA but most of them are talking only Peak amps. How and where can I find more details about these, for example Jump N Carry JNC600 says its peak amps is 1700 watts but no mention about CCA and CAs?
3. We have a small car (4 cylinder), 2 sedans (6 and 8 cylinders) and a commercial vehicle what would be the best option, should I be buy jump starters for different starters for different cars?
4. I see battery packs, power sources and then jump starters in the market. Which one is best? What is the difference? does the battery packs and power sources work the same way i.e. just connecting the jumper cables to the dead battery should work?
5. I have read in one of the articles that not all jump starters are able to start a battery which is completely flat. how do i ensure that the jump starter I am buying will be able to jump start even flat batteries?
6. What cautions I should take when using the jump starter?
7. Which jump starter do you recommend to each of my vehicles?
I will try to answer your questions as efficiently as possible. If there is something that I did not cover, let me know.

1 The specs you should look for is the higher cranking amp rating. This is the actual power that will be used to start the vehicle.

2 Peak power ratings are there to impress people. Always refer to the cranking amps and cold cranking amps when comparing jumpstarters.

3 One jump starter that is capable of starting the largest vehicle is the one you'll want to buy. It will also work well for all of the smaller vehicles. No need to buy multiple units.

4 Battery packs and power sources are just different names for jump starters. They connect in the same way as a jump starter.

5 It is true that not all jump starters are capable of starting a vehicle with a battery that is completely dead. This is another reason to get the jump starter that has the highest cold cranking amp rating, this gives it the best possibility of starting the vehicle with a dead battery.

6 When using the jump starter, connect the positive lead first, then the negative lead. Some units have an on/off switch. These are better because the cables can be connected and then the switch turned on. This prevents arcing and sparking when connecting the cables.

7 Get the jump starter with the highest cold cranking amps within your budget. This will suit the needs of all your vehicles the best.
Customer: replied 6 years ago.
Hi Dave

1. Need some detailed explanation on cranking amp ratings. If the label on my battery reads 660 CCA does that mean the battery will produce 660 Amps of current @ 0 degree Farenhiet? or it requires a jump starter with 660CCA to jump start the vehicle if the battery goes flat? if the later, does that mean your jump starters CA must be atleast equal to the batteries CCA or your jump starters CCA must be equal to the batteries CCA?

In my commercial vehicle I have 2 batteries. Which battery should I use to jump start the vehicle? If I have to use the jump started to fire up both the batteries how do I do it? do I connect the jump starter at the same time to both the batteries and jump start? if so should the CCA of the jump starter must be equal to the sum of both the batteries?

3. If I am buying a jump starter that can jump start the largest vehicle, does that mean need to buy one that has overload tripper so that it will not damage the batteries of the other smaller cars?

5. how to distinguish a jump starter that can jump start even the battery is dead and a jump starter which can NOT jump start a vehicle with dead battery?

6.To avoid connecting the cable the other way round can be avoided if the jump starter has a reverse polarity indicator. Am i right?

7.What brands jump starters have more than 400CCA? as I mentioned one of my car battery reads 660CCA?

Out of curiosity, when we use a jump starter, does the power from jump starter directly flows to the starter motor and makes it work? or the from jump starter is given to the dead battery and the power from dead battery powers the starter motor? how does it work?
1 Cold cranking amps (CCA) is a measurement of the number of amps a battery can deliver at 0 ° F for 30 seconds and not drop below 7.2 volts. So a high CCA battery rating is especially important in starting battery applications, and in cold weather. You do not need a jumpstarter with the same rating as the battery. A lower rating is usually acceptable.

2 The two batteries are interconnected. When jump starting just connect to either battery. Again, CCA can be lower than the sum of the batteries.

3 When using the jump starter, the vehicle will only pull as much power as is needed from the jump start battery. There is no chance of overloading the vehicles electrical system.

5 The higher the CCA rating, the better the chance of starting a vehicle with a dead battery. A jump starter with at leas a 500 CCA rating should be able to start just about any vehicle with a dead battery.

6 Yes, a reverse polarity indicator will let you know if you have connected the cables backwards. This will give you the opportunity to correct the connections before attempting to start the vehicle.

7 Schumacher makes a portabel jumpstarter with 500 cranking amps and reverse polarity protection.

When using a jump starter, power will flow into the dead battery and to the starter motor both, that is why it is harder to start a car with a battery that is completely dead, the dead battery will absorb more of the power.
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