The Cold Cranking Amps is often given as a figure on the battery. To be sure, if you aren’t worried about the weight or cost, you could fit the largest available that will fit with an eyelet terminal that fits the starter post, going for bigger cable is preferable as you say. Martin Scott
Sent from Mail for Windows 10 From: [email protected] Sent: 29 August 2021 19:24 To: [email protected] Cc: Darren Siepka Subject: Re: [Quantum Owners] starter cable current Hi Darren. That seems logical given the cable lengths. Thanks. Fortunately my cable runs will be shorter. I've done a fair bit of digging and like many other such questions the disagreement on the forums is fascinating with debate getting heated! The nearest I can get to any degree of certainty is that the expected current is likely to be under 200A initial peak, dropping rapidly to somewhat less - something in the range 100-150A. These numbers are taken from several threads about similar (and bigger, inc diesel) engines so the chances are they are on the high side but are in a decent ball park. Anyway, it is unlikely to be more and over-estimating current is preferred! Clearly the voltage drop is what is most important, it must be small compared to battery V. I came across this site (which avoids doing calculations the hard way and maybe getting them wrong) https://www.12voltplanet.co.uk/cable-sizing-selection.html which has a calculator. If I calculate based on 1m each way this gives me a V drop of less than 0.25V at 150 A on 25mm2 cable (ie <2% of the voltage). So that looks like a good option. Unless anyone thinks that absurd, I'll give it a go and confirm by measurement. Regards Julian On 2021-08-29 18:27, Darren Siepka wrote: I use welding lead cable for my main lines, especially as I have the battery In the boot. Size wise I use 35 and 50 mm2 cross section. Reason I use welding lead cable is it tends to be more flexible with thicker tougher plastic covering, and best of all usually cheaper too :-) Darren On Sun, 29 Aug 2021, 13:56 , <[email protected]> wrote: Hi My H4 is fitted with a 2L silver top and I want to replace the main power cables (starter and ground). Can anyone advise what the current rating should be? I suspect the existing wiring was for the original Fiesta 1.6 Zetec so potentially is too lightweight. I have found a ~50Ahr battery that fits the original cradle (which was for a ~40Ahr battery). So I must have ~ 20% increase in cranking amps too. Some 50Ahr batteries are able to generate 450A crank current, but I assume (given the options available from suppliers) cables do not have to be rated at this current (and it is short duration). So what is used? Any help appreciated. Many thanks -- -- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/quantumowners?hl=en IMPORTANT NOTE: All information presented herewith is provided on an "As Is" basis, without warranty or the implication thereof. Neither the Quantum Owners Club nor the individuals associated with the Quantum Owners Club or in the preparation of the above information shall have any liability to any person or entity with respect to liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained within this or related message(s). --- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/quantumowners/c426461d1cbcdb73f5801ec1ba4a2090%40cityaudioservices.com. -- -- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/quantumowners?hl=en IMPORTANT NOTE: All information presented herewith is provided on an "As Is" basis, without warranty or the implication thereof. Neither the Quantum Owners Club nor the individuals associated with the Quantum Owners Club or in the preparation of the above information shall have any liability to any person or entity with respect to liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained within this or related message(s). --- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/quantumowners/CABxHo%2By06c4oPAM6YVn57o6b-0TzFb_fDqP6Z6TxDZRUCtk9%3Dw%40mail.gmail.com. -- -- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/quantumowners?hl=en IMPORTANT NOTE: All information presented herewith is provided on an "As Is" basis, without warranty or the implication thereof. Neither the Quantum Owners Club nor the individuals associated with the Quantum Owners Club or in the preparation of the above information shall have any liability to any person or entity with respect to liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained within this or related message(s). --- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/quantumowners/92e76d2c904e49318ca7ca8648c00021%40cityaudioservices.com. -- -- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/quantumowners?hl=en IMPORTANT NOTE: All information presented herewith is provided on an "As Is" basis, without warranty or the implication thereof. Neither the Quantum Owners Club nor the individuals associated with the Quantum Owners Club or in the preparation of the above information shall have any liability to any person or entity with respect to liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained within this or related message(s). --- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/quantumowners/612be9c2.1c69fb81.7b397.669fSMTPIN_ADDED_MISSING%40gmr-mx.google.com.
