73blazer Posted April 22 Report Posted April 22 Why are there three fuses on the lead wires that come with this radio?!?!?!? And the fuse holders are garbage. When I installed this in my K5 Blazer, which I rebuilt and wired completely from scratch myself not using any those kits, all with modern SXL wiring, sealed connectors etc. Anyway, I put a 15 amp circuit to the center console which I built to hold a radio. It has two nice 14ga sxl wires running to it protected with aircraft style circuit breakers (P&B W31 type, almost no fuses on my truck) , when I first hooked this radio up to those wires leaving the factory wouxun leads, standing voltage with truck running was 14.1V and during transmit on high (50w) voltage dropped to 12.3v and the power meter read 34w on GMRS17. I could jiggle the fuse holders and watch the voltage and power jump up and down. I cut off the wouxun leads , the connector and all three fuses, and put my own connector on reconnected it to the same leads in my center console and voltage drop during transmit was 13.9v and power meter read 48w on GMRS17. Leave it to the Chinese to make a really nice radio and put some really crappy fuse holders and connectors to power it. I'll trust my circuit breaker over those crappy fire hazard unsealed fuse holders they use. And why's there three of them!?!??!?!?!?! Quote
Socalgmrs Posted April 22 Report Posted April 22 So you rewired a whole truck custom and only used 14g wire for the radio? You had the opportunity to run 12 or even 10 and you went with 14g. Will it work? Yes but why limit your self? I’m also not going to get into breakers (very slow) in automotive use with barely adequate wire gauge. Ive built custom wire harness from scratch every day for over 20years in on road , off road, crawlers, race trucks and cars, classics and boats. Not once ever have I seen air craft breakers and that’s for a reason. Don’t bother insuring your rig. When it burns down they won’t pay out if they find out you used slow air craft breakers. Also dump the “sealed” connectors I assume something like a gm weather pack or similar and Just crimp solder and water proof shrink wrap I don’t use any “connectors” of any type ever Now to the point, yes they use junk. Yes tear them apart and make a new harness BUT any radio, gmrs cb ham should be wired directly to the battery with a fuse right at the battery on both negative and positive. Then they usually put another one at the radio for some reason (not me). I always use the called out fuse size and one up wire size. Quote
73blazer Posted April 22 Author Report Posted April 22 Well, your allowed to your opinion. I've built many vehicles and I've always used aircraft breakers. The W31 type are far better than any fuse out there. These are not the typical pull type, those are slower. I've compared the specs between what I have and typical auto fuses. But you have your opinions so who am I to try and change them. I used a connector because I move the radio between three vehicles. And it's sealed because I powerwash the inside of my K5. ANd don't worry the spec on the delphi connector is well above it's rated amps, and I use the class above what's called for. But you have your opinions so keep on keepin on. I wired the center console years ago for a CB radio, so 14ga was well enough. It still is for any 15amp circuit. 15amps calls for 18ga min, so I'm really already two gauges higher. It's a short run and as I've indicated, voltage drop at full transmit is .2v, so...14ga is obviously well enough. In a typical vehicle I would agree, direct to battery is best as most acc's outlets use 18ga wire on a 15amp fuse routed through many extra feet of stuff and other connectors. But if you keep doing direct to battery for all your high power accessories, amps, subs, radios, winches, trailer brakes.... etc...etc..etc...you'll have a mess of crap to hook to your battery which causes it's own problems. My circuits are well designed and short. So, it basically is direct to battery. Quote
SteveShannon Posted April 22 Report Posted April 22 37 minutes ago, 73blazer said: And why's there three of them!?!??!?!?!?! Describe them a little better please. I assume two are in series in one wire and one is in the other wire. Which wire has the two fuses in series? What are the markings on each of the fuses? I can only speculate, but I suspect the two fuses in series have different characteristics which combine to provide better protection for different circumstances. If so that’s pretty sophisticated. Quote
73blazer Posted April 22 Author Report Posted April 22 5 minutes ago, Sshannon said: Describe them a little better please. I assume two are in series in one wire and one is in the other wire. Which wire has the two fuses in series? What are the markings on each of the fuses? I can only speculate, but I suspect the two fuses in series have different characteristics which combine to provide better protection for different circumstances. If so that’s pretty sophisticated. All three are the same. Same type and rating. 15amp fuses. Two on the positive lead, one on the negative lead. I almost think the 2nd one on the positive lead was a mistake? I dunno. But interestingly enough, they also give you 6 extra fuses in the box. And I can't say I've ever seen a fuse on the negative lead unless it was a positive ground old ford vehicle. Quote
WRXB215 Posted April 22 Report Posted April 22 6 minutes ago, 73blazer said: And I can't say I've ever seen a fuse on the negative lead unless it was a positive ground old ford vehicle. I'm fairly new to this so I can't say what's common. All I know is my AnyTone AT-778UV has one on each wire. Quote
SteveShannon Posted April 22 Report Posted April 22 6 minutes ago, 73blazer said: All three are the same. Same type and rating. 15amp fuses. Two on the positive lead, one on the negative lead. I almost think the 2nd one on the positive lead was a mistake? I dunno. But interestingly enough, they also give you 6 extra fuses in the box. And I can't say I've ever seen a fuse on the negative lead unless it was a positive ground old ford vehicle. Maybe they had some fuses that didn’t open reliably so they built in redundancy! I think you’re right about it being a mistake. A fuse in each leg isn’t too unusual though. My mobile Yaesu radios have that also. I don’t really know what the philosophy behind it is. Quote
73blazer Posted April 22 Author Report Posted April 22 11 minutes ago, Sshannon said: I don’t really know what the philosophy behind it is. It has something to do with current finding another path to flow via the antenna or it's shielding during high current events, like starting, or winching. They say if wiring radio direct to battery, use fuses on both. If your negative lead is grounded to the chassis, you don';t need a fuse on the negative. I'd have to read more about it to figure out exactly what the scenarios are and why. SteveShannon 1 Quote
SteveShannon Posted April 22 Report Posted April 22 15 minutes ago, 73blazer said: It has something to do with current finding another path to flow via the antenna or its shielding during high current events, like starting, or winching. They say if wiring radio direct to battery, use fuses on both. If your negative lead is grounded to the chassis, you don';t need a fuse on the negative. I'd have to read more about it to figure out exactly what the scenarios are and why. Is the shield of the antenna connector connected directly to the chassis of the radio? If so, that fuse in the negative side wouldn’t see much current if the current does find another path. Quote
73blazer Posted April 22 Author Report Posted April 22 I think what they mean to say is the current could flow through the radio during a high current event with some failure point. If say your negative ground from your starter were to break or corrode badly enough (which is common in older vehicles) , the the current or part of it *could* find it's way through your radio through the negative lead SteveShannon and WRXB215 2 Quote
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