Here check this out. http://www.jalopyjournal.com/forum/index.php?threads/943364/ Posted using the Full Custom H.A.M.B. App!
Most of these are not suitable for automotive work, unless you're interconnecting with mil-type connectors. The 2nd one shown, will do the M24308 rectangular connectors. The best DMC crimp tool for use on cars would be their HX4, which has a big array of positioners for it. I find their Y501 to be the most versatile for insulated lug crimping. You can always call DMC and tell them what you want to crimp and they'll fix you up, but it won't be cheap.
Excellent! I'm subscribed so I look forward to more of your very informative posts. Gotta56forme/Scott
Daniels does make some really nice equipment. And as Bobs396 said, it won't be cheap. Here at work, we have several DMC (Daniels) kits. I want an AF8 crimper for my own use. Then I would be able to use aircraft connectors on my truck. Imagine a quick disconnect connector or two on the firewall, then it would be exhaust, fuel, grounds, and battery cables to remove an engine. Very simple and easy. Mark
The AF8 is a very versatile crimper but the turrets are expen$ive. The smaller AFM8 uses those cheaper button dies, great for any M24308 rectangular or D38999 contacts and many others. There are some nice plastic-shell Amphenol type connectors available from Newark or Digikey that could work well in a bulkhead application.
Agreed that the af8 turrets are expensive. The positioners for the af8m are many. That is more some thing that I am possibly thinking of doing, most likely it won't happen. At work we have whole kits made by DMC, for the Boeing planes and the Airbus planes. The kits come with different turrets for the af8's, positioners for the af8m's, and some of the dies for the hx4 crimper. Insertion and extraction tools are included with wire strippers. Really complete kits in one container. Back to the original subject now.
We have a few DMC sets at work, I've added a lot of odd special turrets, positioners over the years. They also make a smaller crimper, the MH860, not as versalive as the AFM8 bit does really small contacts. The best thing with DMC is, give them a contact/connector part number and they'll come up with the tooling.
I have been to some symposium's where Daniels has set up a booth, they really are helpful and knowledgeable. I have always been impressed with them. I am sure that I have used the smaller crimpers you mentioned, but I don't recognize that base number for the crimper. We may have a different manufacturer of crimper that does the same thing. We recently started doing some quadrax cable crimps for our onboard wi-fi systems. Those connectors take some special tools.
The AFM8 does the smaller crimps and they have a ton of locator buttons for them. Most of them are pretty inexpensive, around $40 per.
Ok, I'm back with more.... sorry about the delay (2 years! Where does the time go!). So.... System Design, Part 6 Component Selection, Part 2 When I left off, the next item on the agenda was fuse panels. One reason I stopped at that point is I needed 'visual aids' and my scanner didn't work at the time. All fixed now, so lets talk about fuse panels. The fuse panel or panels you install are a critical part of the wiring harness, arguably the most important part of one. Get the right panel and install it right and you'll have a safe, reliable system. Get it wrong and the problems can multiply easily. So, what are we looking for in a fuse panel? If you go back and review, I talked about different 'kinds' of circuits, specifically broken into four types; switched, unswitched, continuous, and intermittent. The fuse panel is where you will separate these circuits so in a sense the fuse panel is the 'brains' of the system. This is also where you want to install your overcurrent protection for your branch circuits, providing protection against harness damage. A brief history of automotive wiring is in order here. 'Back in the day', manufacturers started out with basically fuses installed inline on the individual circuits, installed close to the device and not in a central location. Many circuits weren't fused at all (and that's not always bad) and many times the only control on a circuit was the device on/off switch. Over time, the manufacturers started consolidating the fuse locations, eventually putting all fuses in more-or-less one place, which could also allow single-point control (one switch that could turn everything on or off). That has now become somewhat of an industry standard, and is usually what most people rewiring an old vehicle try to achieve. That's certainly the intent behind most aftermarket harness 'kits', but unfortunately many kit designs make that very hard to do if you have anything more than a very basic harness with limited electrical loads. One other thing I'll bring up is WHERE you install the fuse in the circuit is critically important. If you run a hot wire to a device, then install the fuse right before connecting to it, the only part of the wire fully protected is between the fuse and the device; the wire to the fuse has NO short-circuit protection at all. I'll talk about this in-depth further on... Now, most aftermarket fuse panels are of the 'buss' design. This is a single wire coming from your 12V supply feeding the power buss, with one side of each fuse in the panel connected to it. The other side of the fuse has the branch circuit wire/connection. Basically the same design as your electrical panel in your house, just on a smaller scale. You can buy fuse panels with each fuse being an individual circuit, but for anything that's more than a 'basic' harness the wiring can get messy. In nearly all cases, a buss-type fuse panel will be the better choice. So I'm going to assume that's the type panel we're using. So lets look at different ways these can be wired in.... Ok, it's a somewhat crude drawing, but understandable. This is a 'bare bones' harness, just the basics. Lights, horn, ignition, and starting circuits. You have your 12V coming in from the battery, fuses on the various circuits (including the ignition/start). The lights and horn are unswitched (work with the key off) for safety, minimal load on the switch. The #10 wire that feeds the panel (which is what I see used typically) is more than adequate for the total connected load. So what happens when we start adding circuits?
System Design, Part 6 Component Selection, Part 3 Ok, let's step up and add some additional circuits. I would still consider this a 'basic' harness as all we're adding is a couple of safety items (wipers, turn signals) and a few creature comforts (radio and heater) plus some gauges. All of these are switched circuits, so we now need an ignition switch with an 'accessory' position (I showed one above, but it would be unused there). Note that the ignition power is no longer coming out of the unswitched fuse panel, and now we have two wires going to 12V power. At this point, we need to check loads to make sure we're not exceeding current ratings on either the feed wire to the panels or the switch. Now if the vehicle has just two headlights/taillights and one horn, that will put the load on the unswitched panel at about 22 amps, figuring 10 amps for the headlights, 6 for the horn, 4.5 for the brake lights, and about 2 for the taillights. But if you go back to my 'example' car with it's four headlights/taillights and two horns, the load will be over 44 amps. You are now exceeding the current rating of the #10 wire by about 50%... not good. How about the switched panel? Figuring 6 amps for the wipers, 10 for the heater, 7 for the radio, 9 for the turn signals, and 2 for the gauges for a total of 34 amps (and this is with two taillights, not four). Don't forget the ignition (another 8 amps probably) and now you're at 42 amps. Again, not good. Now, one of these loads is intermittent; the the turn signals. So if you deduct that this lowers the loads to 35 amps on the unswitched panel and 33 at the switched panel. Does doing this 'fix' the issue? Not really... What you may find is the headlights dimming when you hit the brakes, and the wipers/heater/gauges slowing or reading wrong when the signals are on. Possibly even a miss in the ignition could show up. I'll talk about calculating feeder loads (wire to the panels) further on. There's one more problem. The ignition switch is rated for 30 amps maximum; we're trying to put 42 amps through it. Derated, the switch is really only good for 24 amps (for safety and switch longevity) so we're exceeding it's continuous rating by about 60%. This switch will run hot, and probably won't last as long as it should. So how do we address these issues? Stay tuned....
System Design, Part 6 Component Selection, Part 4 Ok, in the last installment we left with a system that may work in some cases, but had an overloaded switch. So here's the 'typical' solution. This is the recommendation you'll almost always get from the aftermarket, but unfortunately this defeats the idea on having all your fuses in one place. This will also give you a 'busy' terminal where you connect for your 12V to the rest of the harness. So lets look at it... Ok, here I've added power windows. But this could also be an electric fan or fuel pump, a compressor for airbags, AC or any type/combination of electrical load. There's numerous things I don't like about this. We still have the problem of the overloaded ignition switch, although adding yet another relay on say, the heater circuit, could reduce the load enough to make this work. In essence, you're bypassing the overloaded fuse panel (or it's feed) to remove load. You've now got three (or more) wires connected to your power point, your main power fuses for these circuits are no longer in your fuse panel, and you've added a control wire for each relay. If you're trying to keep your harness simple, it's not working. These limitations are why many vendors like Vintage Air (and others) recommend bypassing the fuse panel and connecting directly to your main 12V power and using a relay to control input power. I'm a firm believer that a harness shouldn't be any more complicated than it needs to be. It certainly makes troubleshooting easier if it's simpler, and there's just less to go wrong. But there's probably thousands of cars out there wired like this, so this will work. So why is this the typical solution? Simple answer, cost. You'll rarely find wire bigger than #10 in any harness kit (except possibly for connecting the alternator output to the battery) because the larger sizes are more expensive, require somewhat more expensive bigger terminals and dedicated crimpers to install them. But now that larger crimpers are available for reasonable cost (HF has a very decent hydraulic unit that will do up to 1/0 wire for less than $100), there's little reason to 'cut corners' if you want a first-class wiring harness. For a better solution, go to the next installment....
System Design, Part 6 Component Selection, Part 5 Ok, now we're going off the beaten path a bit. Some of these parts will probably have to be sourced from somebody other than a typical 'hot rod' aftermarket vendor, but none will be difficult to find or buy, and I'll show some links to what's needed. Who knows, maybe some of them will read this thread and start offering harness kits with these features.... LOL. Ok, here's a diagram that addresses pretty much all the problems. By using just ONE large relay, we can eliminate all relays needed due to an inadequate feed wire to the panel, and drop the load on the ignition switch down to just the ignition load and the load of the starter solenoid and relay coil loads, which will be less than 12 amps total. You now have just one wire connecting to your 12V power point (albeit a large wire), and all of your branch circuit fuses are now in the fuse panel except for the ignition if you want to fuse that. You may still have a problem if the load on a fuse panel exceeds the size of the furnished wire, but that can be addressed too. So, lets do an example; this is where you use all the branch circuit info I had you collect... LOL. I'll use my 'example car', so if you recall from post 75, I had 48.3 amps on the unswitched panel, and 53 amps on the switched panel. Well, that #10 wire 'typically' found feeding aftermarket panels is now suspect, but we'll see if it'll work. Now, they may be adequate for your application, but you need to check. So what to do if it's not? Let's change panels..... look here: http://www.wiringproducts.com/fuse-blocks Scroll down to the Bussman 'ganged' panels. You can get these from 6 to 12 fuses, with panel ratings of up to 105 amps! Note also that the incoming power connection is bolted, with tab connections for the branch circuits. These tabs are good for up to 30 amps which should be adequate for nearly any circuit. But you say 'I don't want to build my whole harness! The kits come with marked wires telling me where they go!' First, are those wires big enough for the intended circuit? You may be replacing some of them anyway. But if not, simply cut the supplied fuse panels off and re-terminate the wires to the new panels. Now, some may be crying about the cost of the panels. Think about it... Both panels shouldn't cost more than about $55, what will all the relays and extra wire cost you? As I said earlier, why scrimp on your wiring seeing how it can burn your car down? Would you cut corners on the brakes, suspension, fuel system? I would hope not.... Where do you find the large relay? No problem.... http://www.mcmaster.com/#general-purpose-relays/=zrqok5 Note that you can get up to 200 amp rated relays, but for most purposes the 100 amp relays will be fine unless you have a lot of motor loads. Now, some will notice that these resemble Ford starter solenoids, which can be gotten cheap or free. The Ford relays are not rated for continuous duty, and coil failure may occur. I'll talk about relay ratings and calculating feeder wiring size in the next installment....
System Design, Part 6 Component Selection, Part 6 Ok, so you've got four different diagrams to install the fuse panel. Which way will be best will depend on your loads and number of branch circuits. The two main issues are what size wire do you need for your feeder wire or wires, and avoiding overloading the ignition switch or any other switch contacts i.e. relays. Now I talked previously about 'diversity', and how this can be used to reduce wire sizes in some cases. But because these are loads that don't stay the same as different circuits are switched on or off, we need to revisit switch and relay ratings. Switches and relays have maximum amp ratings. Again, for long life and reliability they have to be derated to 80%. Again, any plug-in 'cube' relay is only good for 30 amps maximum because that's the max rating for any wire/wire connector you can plug into it. Now, you will find some plug-in relays with legitimate ratings above 30 amps, typically 40 amps. These are designed for 'high inrush' applications (generally motor loads) where instantaneous current can be 300% or more of the running current. These have heavy-duty contacts to withstand that current, but are not designed to carry it continuously. Personally, I wouldn't use any relay that's not designated as 'high inrush' or 'high amp DC' in any automotive application. So why is this a concern? If you have a switch or relay controlling a load, if you have an intermittent load that load has to be included with the continuous load when sizing the switch/relay. As an example, if your ignition switch is rated for 30 amps, derated it's now good for 24. Apply a 20 amp continuous load and you're good to go. But if you have an intermittent load of 16 amps also connected, when that load is switched on your load is now 36 amps. Even a intermittent load if switched often enough will significantly reduce switch contact life if not cause outright failure. Now, if you have multiple intermittent loads (not all which may be used at the same time) you don't need to add all of them, but you do need to add any that may feasibly be on at the same time to determine switch or relay rating. So let's figure out our feed circuits to the panels. I'm going to skip over diagrams 1 and 2 as the same calculations as I'm using for 3 and 4 will apply; I'll leave those two as a exercise for the student... LOL. For the diagram 3 calculation I'm going to go back and use my 'example car' from post 75 as this represents somewhat of a 'worst case'. If you recall, this car has almost everything; 4 head/tail/brake lights, emergency flashers, radio, heat/ac, power windows/seat, etc, etc... So my continuous load on the unswitched panel is 35.5 amps, and I'm going to add in the largest intermittent load at 16 amps (rather than derating it; this will give a bit more 'headroom') for a new total of 51.5 amps. Using the 'supplied' #10 wire and an assumed length of 6' to get from the panel to the 12v power point, this will give me a calculated voltage drop of .31V and a percentage drop of 2.25% in the feeder wire (You did remember to save that voltage drop calculator to your 'favorites', right? And remember that voltage drops add up; with 2% here and if you have 3% in your branch circuit, a device at the end of that circuit will be down 5%). You want to keep the feeder drop right around 2% if possible, this is acceptable. I'll note that adding a mere 3' to the length of the wire will increase the drop by another percent, and in any case you may see some dimming if two intermittent loads are on at once. If you mount the panel where your wire length goes up, you may need a larger feeder wire to keep drop down. Moving on to the switched panel, we have a continuous load of 53 amps plus another 16 amps for the largest intermittent load for a total of 69 amps. Well, we're already in trouble; you can't run even the 53 amp load through the ignition switch, so we'll have to bypass the fuse panel for some circuits and use relays fed directly from the power point. The ignition (which has to go through the switch), wipers, and gauges add up to 22 amps (under our switch derated 24 amp max), so all the rest have to be powered through relays. That's at least four relays, there's only two circuits still left in the fuse panel, and you have at least 6 wires now connected at your power point. Messy.... I didn't do a feeder calculation for the panel as the load is well under the capacity of #10. Calculate your feeder loads to the relays the same as a branch circuit, just keep your voltage drop down. So let's look at the last diagram, 4. Because we're using just one large relay, this can be mounted close to the panels. I'm going to assume a 6" wire length from the panels to the lugs on the relay, so what do we get now? So at the 51.5 amps number on the unswitched panel, drop is only .026V and the percentage is only .2% ! Even if you add in another large intermittent load, it only goes up about another .01V! Excellent! You have almost identical numbers at the switched panel, so the drop/percentage is almost exactly the same. And in both cases the drop is small enough to produce very little heat in the wire (under 2 watts). So all we need to do is figure out the feeder wire from the power point to the relay size...
common steve ....already signed up for this semesters class posted 11-12-2015 so far I like it , making it easier for me to think what I am going to do .
Just read thru this thread, great job Steve, thanks for taking the time to put this all down for everyone, what a cool thing to do. Are you going to go any deeper into drawing up a schematic or wiring diagram? IMO it's a critical step that really needs to be done. In any case, great job once again, this is a tremendous resource.
Thanks for the work so far, Steve. It's been worthwhile to read & study, a very good thread. & I don't have a lot of problems w/wiring. Trouble-shooting, maybe sometimes. Get to do it on city buses. Talk about being f-d up... ;( ... Marcus...
For big posts that require lots of time, its a sanity saver to work on them in a word document on the Pc then copy into a post. This is a great thread
System Design, Part 6 Component Selection, Part 7 We left off needing to calculate the feed wire size from the 12V power point to the relay in diagram 4. We also need to determine how big of a relay we need, but we'll start with the wire.... So the first thing to do is add all of your continuous loads up, both panels. So, adding our numbers together, we get the scarily large amount of 88.5 amps. Don't forget to add the largest intermittent load, in this case 16 amps, for a grand total of 104.5 amps. Phew! That's a lot! If you apply the derate, 104.5 x 125% comes out at 130 amps! You're talking 1/0 wire here.... Do we really need wire that large? Let's look.... So using the voltage drop calculator and again assuming a 6' length from the power point to the relay, the drop with 1/0 wire is a minuscule .06V at only .45%. We want to keep drop at 2% or less, let's see what a smaller wire will do. If we reduce to #2, voltage drop is now .09V at .71%. #4, drop is .16V at 1.16%, go to #6 and it's .25V at 1.81%. Any of these will work, but the price difference is minimal between 6 and 4, I'd recommend using #4, particularly if you want overcurrent protection on this wire (I address this below). I'd also recommend that the power wire from your alternator to the battery be sized the same. That wire should be sized to at least the total of all your continuous loads to keep voltage drop to a minimum, particularly if you're using a one-wire alternator. If you're using a three-wire alternator with remote sensing, it will compensate somewhat for the drop, but don't get carried away.... Where can you get this wire? I'd recommend welding cable because of it's durable insulation and flexibility, and most any welding shop should have it or it can be ordered online. I'll also note again that your alternator and/or charging system should be capable of producing 125% of the total connected continuous load, both for being able to 'make up' power used by intermittent loads and for long life. Relay size? Remember, we can't exceed it's maximum rating and because of the 88.5 amp number above (which must be multiplied by 125% for 110 amps), a 100 amp relay won't do here. McMaster-Carr sells a 200 amp DC 'high current' relay (part # 7995K31, about $60), as do others. I'll also mention that using diagram 4 will eliminate relays being needed for supplying power when bypassing the fuse panel, but you still may need some on some circuits due to switch or control limitations, but they can be fed directly out of the fuse panel. One last thing before moving on to wiring methods. Do you want overcurrent protection in those feeder wires? If you're using #10 wire (or similar smaller sizes) for your feeders, I would definitely install protection. If you're using one large wire, if it's routed carefully and protected from damage, you could get away without it. So if you want protection, the question is what kind of protection? Fuses or Fusible links? Fuses may or may not be a good choice. Fuses will only blow when their maximum rating has been reached (or at least 90%+ of that rating). So what if the wire rating is less than the fuse size? In that case, if you have a partial short or an overload, the wire will be subjected to that overcurrent until current rises far enough to blow the fuse, which may result in damage or even fire. This is where fusible links come in; they will withstand an overload for a limited time (depending on how much/how long), while still protecting the wire but not interrupting the circuit. Let's do an example... Let's go to diagram 4. Using a #4 wire as our feeder wire, it's rated at 70 amps. Well, we know we can't use a 70 amp fuse as our continuous load is bigger than that. So what size do we need? If you take the continuous load plus the largest intermittent load, you're at 104.5 amps. Multiply that by 125% and you're looking at a 130 amp fuse. Will that fix it? Maybe, maybe not. Add in your next-largest intermittent load just to be safe; now we're at almost 119 amps and a 150 amp fuse. So at this point, you've got that #4 wire fused at over double it's rating. In a direct-short-circuit situation, the fuse will blow, protecting the wire. But what if you only have a partial short? That fuse won't blow until it sees around 135 amps at least, you can cook that wire to the point the insulation burns over a longer time. A fusible link rated for just the continuous load or maybe the next size up should hold a intermittent load, but will clear a overload or partial short if it goes on long enough and before damaging the wire. A link will also clear a direct-short-circuit quickly enough to protect the wire. On feeder wire sizes smaller than #6, I would not under any circumstances fuse them larger than their rating, but I would use a fusible link rather than a fuse to hopefully eliminate nuisance tripping. This is generally where/why the OEMs use fusible links when they do use them. Now, I'm going to add one very large caveat to this; I can't find any information on the 'slope' of a fusible link. This would be a chart that shows how quickly it would 'clear' (blow open) a overload or how much of a overload it can withstand before blowing. I would assume that the smaller the overload, the longer it would take to blow, that's why the OEMs use them. If you decide to use a fusible link, I'd use a feeder wire no more than two sizes smaller (in this case, #2) for the calculated load to avoid having too much difference between the wire rating and the link rating. Otherwise you may not have any more overload protection than what a fuse offers (which is basically zero). Lots to digest here, if there's questions let's have 'em before moving on....
I'm in the process of designing my wiring on my F100. This thread has been a great help as all I know about vehicle wiring is, the bigger the wire the bigger the smoke cloud. Thanks for the help Crazy Steve
Fantastic, Steve, thanks! Only made it to post #64 thus far, but looking forward to the rest. Great resource.
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