Kelley's Works in Progress
ANL Fuse Retrofit Kit
If you're here, you probabaly followed the link from the pricing page, or from the main page, and you're wondering just what this kit is meant for, right?
It's simple. I think every vehicle I've worked on made since 1957 has had some sort of fuse protection in the alternator circuit, with the ability to isolate the alternator from the rest of the vehicle. Why? Because alternator output is proportional to the voltage applied to the field coils.
Field coil voltage is typically 4VDC or less, as I recall. This is metered by the voltage regulator. However, if you should suddenly - for some reason - get full battery voltage to the field coils, you'll see a surge of up to 90VDC and possibly several hundred amperes! This would be a Very Bad Thing™. How Bad? On modern computer-controlled vehicles, you could end up blowing just about all of the circuits in the computer!
Enter the ANL Retrofit Kit. If you're going to replace your alternator lead, it is the opinion of just about everyone with any mechancal background that you need an ANL kit - or sometime similar! If you can't spring for the kit, replace all the other mains and do the alternator lead later - when you can afford to get the ANL kit. Beancounters are always trying to design things "out" of vehicles to save a few bucks a unit - but this has been around for the last 50 years or so, and I have to assume there's a reason why.
What is an "ANL Retrofit Kit?" As I sell it, it's simply an ANL fuse block, mounting hardware, an 18" lead (to go from the ANL fuse block to the distribution point for power) and it includes an ANL fuse. If you get the ANL kit and the alternator output lead at the same time, we'll also extend the alternator output lead by 6" - to give you a little more flexibility in mounting the fuse block (the kit was devised on a RENIX vehicle - and Chrysler decided that the location I liked for the ANL fuse block would be a good place to put the vacuum servo for the cruise control. No, I don't know why, either.) Instructions are provided with the kit, and may be found as a .pdf file on the Instructions page as well.
Let me say this again - If you can't afford to replace all the mains and get the ANL kit at the same time, it's a lot better to wait on the alternator output lead until you can get it and the ANL kit together! I'd really rather you didn't remove a fuse on your vehicle. Besides, You Have Been Warned™, and WiP cannot and will not assume or accept any liability for any damage that may result from such removal (we offer a replacement option, and you've got a couple of ways to go about the job - so pick one.)
Another reason for the ANL kit is to allow for alternator upgrades. True to form, the accountants at these outfits will allow "just enough" wiring for the current under OEM specifications. If you upgrade from, say, a 90A alternator to a 136A unit, the first time you swing to full output you're running a good chance of blowing out the fusible link. If you have the PDC with a pair of MAXI60 fuses marked "Generator," it's just become a very good chance (since it's only 120A combined.) Going to the ANL fuse will allow you to install a much larger fuse, and it's easier to find and install the 10AWG fusible link wire used on other models (that's the green wire going to the PDC stud.) I try to keep ANL fuses up to 200A on hand, and we've seen them in ratings up to 600A (which you can even use on winches, if you're cranky. We've got current draw data for winches by make, model, and weight being pulled - and you can install a fuse to protect your winch from overwork.) To select a fuse for your kit, you simply get one that is the same nominal rating as your alternator, or the next rating higher. (The 136A from our demonstration would take either a 140A or a 150A fuse - both are available, and it largely depends on what I have on hand at the time.) Note that alternator "true" output can vary by as much as -5/+10% from the "nominal" rating - again, using our 136A unit, I can see actual output of 130-150A from the thing. That's also at the nominal operating voltage of 13.6-14.5VDC.
ANL fuses can (usually) be had in ratings from 60-600A, in various steps. I try to keep fuses from 100A-200A on hand, and if there is enough demand (there is currently none) for lower ratings, we'll start carrying 60A and 80A as well. Higher ratings are likely to remain Special Order items - but I can probably still get them a bit cheaper than most retail vendors (for instance - an ANL150 from me is $7 - I've seen them locally for $15-20! And, I'll ship them First Class Post for free - priority for fuses only would run you five bucks.)
When getting an ANL fuse kit, I do recommend that you get at least one spare fuse. If you're planning it as part of an upgrade that's on the horizon; get a fuse for what you currently have, and one to satisfy your future upgrade. You can replace the fuse with the higher rating when you upgrade, and save the "smaller" fuse for a "limp home" fuse until you get a spare - the alternator will only generate the current that the regulator thinks the system needs, so you can turn a few things off and get home on the smaller fuse without incident.
I think that's everything you'll need to know - for now. If I missed anything you'd like to know, drop me a line and ask away - the worst I can say is "let me find that out for you."