Keep me from doing something stupid in my 2017 Tahoe

[wm8s]

I'm about to nerdify the 2017 Tahoe C1500 Premier, and I wanted to run my notes by the Panel of Experts [that's you] to make sure that I'm not about to do something really stupid.

The overall setup will initially be an AnyTone ATD578UV, two Uniden SDS200 scanners, and a Midland 75-822 chicken band radio [I wanted so much to like the Uniden CMX760, but it gets absolutely trashed in Amazon reviews for locking up]. I might do an ICOM IC-705 and 250W amp in "Phase 2", so I'm leaving room to upgrade to that in the future.

I'm running Powerwerx 6-AWG red+black from the battery + and - [that seems to be the consensus, for both quality of power and to avoid load sensing issues with the GM charging system], to a MAXI fuse block mounted adjacent to the battery, in nylon loom probably along the top back of the engine compartment wire tied to the existing loom, through the firewall grommet's nipple, thence under the center console to the center console's compartment. I'll terminate that with PP75 PPs [6-AWG won't go in PP45s], then use a short PP75-to-PP45 to the RIGRunner [below].

At the bottom of the center console's compartment, I'm mounting a Stridsberg MCA204M 4-port RF distribution amp [to split one scanner antenna to the two SDS200s and two spare pigtails for guest scanners], and a RIGRunner 4008 8-port 12 VDC distribution block [ATD878, SDS200 x2, CB, RF splitter, IC-705 {future}, and two PP pigtails for guest equipment]. I'm leaving room for a 70A 2-circuit splitter if I later decide to add a 250W HF amp.

I'm using a Havis C-VS-1000-GMC-1 center vehicle console bezel, to which will be mounted a Havis C-EB40-SDS-1P bracket set for the 878 and two Havis C-EB20-156 faceplates for the SDS200s.

I'm mounting five ICOM SP-35 speakers, two high up on the driver's side knee bolster [pointing toward me], one on each side of the center console [pointing up], and one [future] as yet to be determined.

I haven't settled on antennas; I might do temporary thru-glass [yeh... cringe] until The Plague subsides and I can have somebody punch a bunch of NMO mounts in for me.

Where are my mistakes?

Thanks in advance!

...R

 

[Mr_Boh]

This is more of an opinion but I would not use PowerPoles. PowerPoles are designed for quick connect and disconnect. I would use fuse blocks and distribution blocks that are designed for mobile or marine use. Cheaper too

 

[wm8s]

This is more of an opinion but I would not use PowerPoles. PowerPoles are designed for quick connect and disconnect. I would use fuse blocks and distribution blocks that are designed for mobile or marine use. Cheaper too

That's a good point. I had planned on using the appropriate retaining clips on all of the PowerPole connections inside the console. That should greatly reduce the possibility of something popping loose. Do you have some other concern, like the quality of the connectors, that I should be thinking about? Exactly the kind of stuff I'm looking for. Thanks!

 

[ems55]

This is more of an opinion but I would not use PowerPoles. PowerPoles are designed for quick connect and disconnect. I would use fuse blocks and distribution blocks that are designed for mobile or marine use. Cheaper too

Great idea !! Any suggestions????

 

[mmckenna]

I've done a number of installs, including Chevy pickups of this era. My -opinions- below. Take them with a grain of salt and do what you want with it:

I'm about to nerdify the 2017 Tahoe C1500 Premier, and I wanted to run my notes by the Panel of Experts [that's you] to make sure that I'm not about to do something really stupid.

The overall setup will initially be an AnyTone ATD578UV, two Uniden SDS200 scanners, and a Midland 75-822 chicken band radio [I wanted so much to like the Uniden CMX760, but it gets absolutely trashed in Amazon reviews for locking up]. I might do an ICOM IC-705 and 250W amp in "Phase 2", so I'm leaving room to upgrade to that in the future.

I'm running Powerwerx 6-AWG red+black from the battery + and - [that seems to be the consensus, for both quality of power and to avoid load sensing issues with the GM charging system],

Do not run your negative lead direct to the battery. If you check the GM upfitter guides, they'll tell you to ground to the chassis at the point where the battery ground strap is connected. Connecting directly to the battery bypasses the hall effect sensor.

But, you'll also likely find that GM has some words about how much return path current they'll be happy with you running back to the chassis. The ground strap for the battery may not be large enough. That may mean running a new upsized strap through the existing sensor to ground.

I have the Uniden CMX560 and never had any issues with it locking up, but I haven't used it in a while. Not sure they still sell it, but it's the little brother of the CMX560 and doesn't have weather band. If you can find one of those, it may be a suitable solution. I don't think they are outstanding radios, but for a basic CB, it worked fine. I had the RF deck portion of it behind my rear seat with my others and used an RJ-45 Ethernet cord to extend it up to the front. I had an RJ-45 jack low down on the dash and could plug/unplug the hand held control head as needed.

to a MAXI fuse block mounted adjacent to the battery, in nylon loom probably along the top back of the engine compartment wire tied to the existing loom, through the firewall grommet's nipple, thence under the center console to the center console's compartment. I'll terminate that with PP75 PPs [6-AWG won't go in PP45s], then use a short PP75-to-PP45 to the RIGRunner [below].

I'd skip the Powerpoles. Unless you intend to be ripping and replacing parts a lot, using unnecessary connections adds to voltage drop. It's also unnecessary costs, in my opinion. I'd run your #6 straight to a fused distribution block:
https://www.amazon.com/Blue-Sea-Blade-Block-Cover/dp/B01C7A8PT8/ref=sr_1_38?dchild=1&keywords=BlueSea+fuse&qid=1597600781&refinements=p_89:Blue+Sea+Systems&rnid=2528832011&sr=8-38

At the bottom of the center console's compartment, I'm mounting a Stridsberg MCA204M 4-port RF distribution amp [to split one scanner antenna to the two SDS200s and two spare pigtails for guest scanners], and a RIGRunner 4008 8-port 12 VDC distribution block [ATD878, SDS200 x2, CB, RF splitter, IC-705 {future}, and two PP pigtails for guest equipment]. I'm leaving room for a 70A 2-circuit splitter if I later decide to add a 250W HF amp.

70 amps for the amplifier plus all your other gear is going to be really pushing the capacity of your 6 gauge. Unless you are really confident you'll be adding the amplifier down the road, skip it. You'll want a dedicated feed for that, maybe even a secondary battery.

I'm using a Havis C-VS-1000-GMC-1 center vehicle console bezel, to which will be mounted a Havis C-EB40-SDS-1P bracket set for the 878 and two Havis C-EB20-156 faceplates for the SDS200s.

I'm mounting five ICOM SP-35 speakers, two high up on the driver's side knee bolster [pointing toward me], one on each side of the center console [pointing up], and one [future] as yet to be determined.

Beware of air bag deployment zones. Also beware of smacking your knees against the speakers every time you get in/out of your truck.
If you want separate speakers for spacial diversity, you may want to rethink your setup. Putting the speakers spread out a bit more will help. I'd keep them off the dash board if you can. You can tuck them under seats, behind the rear seat, other tricky places. A bunch of speakers in plain view is going to look pretty odd in my opinion.
Other option is to combine them into one or two speakers. You can get small audio mixers/combiners and small 12 volt amplifiers that will do a lot of this work for you. RDL Labs makes some nice products that may simplify your install: RDL Homepage

I haven't settled on antennas; I might do temporary thru-glass [yeh... cringe] until The Plague subsides and I can have somebody punch a bunch of NMO mounts in for me.

Yeah, cringe.
Glass mount antennas won't play well with tinting. Glass mount CB antenna downright suck. Dual band glass mount antennas are large, 1/2 wave on VHF, so they tend to get ugly in short order. I'd skip those and go straight to the NMO's. They are not hard to install on your own. You can get a 3/4" hole saw from Home Depot and probably knock them all out in an afternoon. If you were local, I'd offer to do them for you. It's not hard, just takes some planning. Measure thrice, drill once.

Where are my mistakes?

Other than the 70 amp current draw through the #6, I don't see any mistakes, just difference of opinion. You do what works for you.

Some things I'd suggest:

Ground each radio chassis independently to the vehicle chassis with the shortest lead you can. This can help with all kinds of weird issues and gives a nice short path for RFI to ground, rather than relying on a long conductor run back to the battery.

If you are going to drill holes in the roof of your truck, don't try and save $5.00 by going with cheap Chinese antenna products. Do it once, do it right and you'll never question them. Stick with Laird, Larsen, etc. Do not use Tram/Browning or any of the hammy/hobby grade stuff.
Same with the antennas. The Larsen NMO-150-450-800 is a good choice for your scanners. For the CB, Larsen NMO-27, accept no substitutes, no matter what the golden screwdriver at the truck stop says. Make sure you figure in a spare NMO mount or two, as you'll find your needs may change.
Carefully consider antenna layout and spacing before the drill touches the body.

While it's an expense, consider getting a pair of crimpers that will handle 6 gauge wire. A properly crimped connector will be a thing of beauty and will prevent issues down the road. For my personal use I bought a set of antique crimpers that will do 8, 6, 4 and 2 gauge really cheap off E-Bay. That and a stock of crimp lugs has worked out well. Also, make sure you cover all the crimps with marine grade/adhesive lined heat shrink tubing. It'll protect things and make for a nice looking install.

Good luck!

 

[K7MFC]

While it's an expense, consider getting a pair of crimpers that will handle 6 gauge wire. A properly crimped connector will be a thing of beauty and will prevent issues down the road.

+1 for this bit of advice. Crimp tools are a solid investment for your tool box. I've acquired crimpers and various dies over the years for different coax types, wire, network cable, etc. I use them all the time! Quality wire strippers and coax strippers are a must-have as well.

 

[a417]

I'm running Powerwerx 6-AWG red+black from the battery + and - [that seems to be the consensus, for both quality of power and to avoid load sensing issues with the GM charging system], to a MAXI fuse block mounted adjacent to the battery, in nylon loom probably along the top back

70 amps for the amplifier plus all your other gear is going to be really pushing the capacity of your 6 gauge. Unless you are really confident you'll be adding the amplifier down the road, skip it. You'll want a dedicated feed for that, maybe even a secondary battery.

Second [suitable] battery in the back (or other suitable location) with a battery isolator sounds like the safer bet. Run all the toys off the second battery, let the isolator charge it and maintain voltage and leave the OEM battery to deal with the rest of the GM shenanigannery.

 

[wm8s]

Great ideas.

250W HF was a pipe dream, anyway, and I think the gist of the comments is that it'll be a massive hassle. In fact, HF period is not all that likely, which leaves me at only ~15A total. Even if I were to put in a 100W HF rig, that'd only take me to ~35A.

At 15A, does that allay the concerns about the ground wire sensing / charging? I'll leave a little slack in the ground wire, and if I put in HF, I'll revisit the DC grounding issue then.

I'm fine with the PowerPoles. Cost isn't an issue; I'll make sure I use locking clips; and at these low currents, IR drop won't be an issue.

I'm using ICOM SP-35 speakers, and they're tiny [but sound pretty decent]. I've already removed the driver's side knee bolster, and there aren't any airbags. And I'm pretty sure I won't crash my big fat legs into them where I'm putting them. Stealth speakers would be nicer, but these aren't intrusive, and they'll sound a lot better.

I think y'all have convinced me to go straight to NMO mounts. I put 7 Larsen's on the top of my last Tahoe, with all Larsen antennas, and that setup worked great; cost is not an issue. But it's not an especially easy one-man job, and with The Plague as it is, I'll have to let a contractor do it.

As for crimping, I'd planned on only soldering everything given that I don't have a crimper [but can get one if I need to]. I have SELTERM 6 AWG ring terminals (#10 for the fuse block, and M8 for the battery lugs). What's the best thing, cost notwithstanding: crimping only, soldering only, soldering and then crimping, or crimping and then soldering?

Thanks again!

...R

 

[mmckenna]

Great ideas.

250W HF was a pipe dream, anyway, and I think the gist of the comments is that it'll be a massive hassle. In fact, HF period is not all that likely, which leaves me at only ~15A total. Even if I were to put in a 100W HF rig, that'd only take me to ~35A.

At 15A, does that allay the concerns about the ground wire sensing / charging? I'll leave a little slack in the ground wire, and if I put in HF, I'll revisit the DC grounding issue then.

No. The issue is you are creating a path back to ground that bypasses the sensor. Your radio will be grounded to the chassis through the antenna mounts, so that gives an alternate path other than using the one going through the sensor.

I'm fine with the PowerPoles. Cost isn't an issue; I'll make sure I use locking clips; and at these low currents, IR drop won't be an issue.

It's up to you, but it's sort of pointless to have unnecessary connections/splices where you don't need them. Powerpoles are not going to add anything to your system.

As for crimping, I'd planned on only soldering everything given that I don't have a crimper [but can get one if I need to]. I have SELTERM 6 AWG ring terminals (#10 for the fuse block, and M8 for the battery lugs). What's the best thing, cost notwithstanding: crimping only, soldering only, soldering and then crimping, or crimping and then soldering?

Crimping is always preferred. Solder stiffens the cable when it wicks up the strands. Not a good thing to have in an environment with vibration. I do know from others here that soldering is forbidden for connecting wires/coax/etc. on aircraft due to that issue.
Using crimp terminals designed for the conductors you are using with a proper crimp tool will give you 'gas tight' connection that are not only mechanically sound, but proven to be low resistance connections. I run large -48vdc power systems at work that use 500MCM sized conductors, and we -only- do crimp connections.

 

[wm8s]

No. The issue is you are creating a path back to ground that bypasses the sensor. Your radio will be grounded to the chassis through the antenna mounts, so that gives an alternate path other than using the one going through the sensor.

I obviously don't understand where the Hall effect sensor is. [Pardon my drawing talents, which have not improved even marginally since first grade.]



If the sensor is at the orange location [I doubt it; Chevy {and I tentatively} bolted right onto that big "fuse" block that sits right on top of the battery], then won't it sense all returning current, including whatever if any that goes from the radio, up the coax shield, through the mount, into the frame, back to the frame strap at the battery, and back to the battery [in the world of voltage dividers, will any significant current really prefer that return path to #6 copper wire?]?

And if it's at the purple location, then won't it miss my tap and fail to take all of my added loads into account, causing the problem that we're trying to avoid?

It's up to you, but it's sort of pointless to have unnecessary connections/splices where you don't need them. Powerpoles are not going to add anything to your system.

The value to me [admittedly minor as it is] is the ability to quickly yank the radios out in case I need them separated from the truck [either to use at an extended field assignment for my agency, or if there's a problem that requires their immediate removal], plus it'll save me having to redo everything when I eventually replace them with something shinier and sell/repurpose them. I know it's not much, but I also haven't really heard any downside other than a little cost [which I don't care about] and voltage drop [which will be very tolerable at these loads (all <1A but one at 10A)].

Don't get me wrong; these are all great ideas, and I had to think hard about them all. So please don't think I'm dismissing anything; I really appreciate the feedback. I've already made a number of changes based on everyone's help.

...R

 

[mmckenna]

I obviously don't understand where the Hall effect sensor is. [Pardon my drawing talents, which have not improved even marginally since first grade.]

View attachment 90015

If the sensor is at the orange location [I doubt it; Chevy {and I tentatively} bolted right onto that big "fuse" block that sits right on top of the battery], then won't it sense all returning current, including whatever if any that goes from the radio, up the coax shield, through the mount, into the frame, back to the frame strap at the battery, and back to the battery [in the world of voltage dividers, will any significant current really prefer that return path to #6 copper wire?]?

And if it's at the purple location, then won't it miss my tap and fail to take all of my added loads into account, causing the problem that we're trying to avoid?

Maybe I misunderstood your post, but it sounded like you wanted to connect directly to the negative battery post. If you are going to connect to the existing body ground point, then that won't be an issue. The Hall Effect sensor is at the orange box location. As long as you don't bypass that, it's not an issue. Just be sure that if you do add the amplifier down the road, you consider the amount of current passing through the battery - post strap to chassis ground point.

The value to me [admittedly minor as it is] is the ability to quickly yank the radios out in case I need them separated from the truck [either to use at an extended field assignment for my agency, or if there's a problem that requires their immediate removal], plus it'll save me having to redo everything when I eventually replace them with something shinier and sell/repurpose them. I know it's not much, but I also haven't really heard any downside other than a little cost [which I don't care about] and voltage drop [which will be very tolerable at these loads (all <1A but one at 10A)].

Don't get me wrong; these are all great ideas, and I had to think hard about them all. So please don't think I'm dismissing anything; I really appreciate the feedback. I've already made a number of changes based on everyone's help.

Not a problem.

I don't see where you mentioned the removability of radios as one of the goals in the earlier posts. Maybe I missed it. If that is a requirement, then a suitably sized Anderson Powerpole would be an option.

My point, previous to knowing that was a requirement, was that I see amateurs putting powerpoles all over the place. They certainly have their applications, but rarely in mobile installs. Most of us don't remove radios once they are installed. There are better/cheaper solutions for static mobile installation.

As for the removability, sounds like a hassle with the 5 speakers, antenna connections, multicoupler, etc. Mounting all that in the center console and then pulling it out periodically sounds like a pain.

 

[wm8s]

You didn't miss anything. I did plan on mounting my black wire directly to the battery. I'll go out and see if I can find the sensor, and figure a way to get it between me and battery. Thanks!

 

[mmckenna]

If you want to give yourself a headache, or cure insomnia, read this:

Electrical | Caltrans

State of California

dot.ca.gov

CalTrans has a nice set of specs for wiring vehicles. Well thought out, well proven, and pretty extensive. No applicable to hobby use for the most part, but there's some really good stuff to learn in there.

 

[phask]

No. The issue is you are creating a path back to ground that bypasses the sensor. Your radio will be grounded to the chassis through the antenna mounts, so that gives an alternate path other than using the one going through the sensor.



It's up to you, but it's sort of pointless to have unnecessary connections/splices where you don't need them. Powerpoles are not going to add anything to your system.



Crimping is always preferred. Solder stiffens the cable when it wicks up the strands. Not a good thing to have in an environment with vibration. I do know from others here that soldering is forbidden for connecting wires/coax/etc. on aircraft due to that issue.
Using crimp terminals designed for the conductors you are using with a proper crimp tool will give you 'gas tight' connection that are not only mechanically sound, but proven to be low resistance connections. I run large -48vdc power systems at work that use 500MCM sized conductors, and we -only- do crimp connections.

FWIW - I worked for 20+ years for an Auto Tier 1. One of the divisions assembled wiring harnesses. I visited and did some work there over the years. They did some very large gauge pieces. These had the lugs soldered. They were done by hand by dipping the entire wire with the lug attached into molten solder. I cannot remember if they were crimped as well or not. I have some pigtails around here that were surplus that are 4 gauge or so that I'll have to look at.

One factory had 100 or machines that did nothing but cut, strip and terminate wires. There also were many hand-operated crimping machines.

I can't explain who,what or why, but at one time, some auto/truck manufacturers specified solder.

 

[mmckenna]

I can't explain who,what or why, but at one time, some auto/truck manufacturers specified solder.

Absolutely. If you read the CalTrans document I linked to above, soldering is an option, but it requires supporting the joint to keep it from flexing.

Soldering large gauge conductors like that takes some skill. Too much solder and it wicks up the strands and then you've got issues. Hard for most people to do correctly.
On the other hand, crimping is established as a proper connection when it's done to manufacturer specs.

 

[phask]

Absolutely. If you read the CalTrans document I linked to above, soldering is an option, but it requires supporting the joint to keep it from flexing.

Soldering large gauge conductors like that takes some skill. Too much solder and it wicks up the strands and then you've got issues. Hard for most people to do correctly.
On the other hand, crimping is established as a proper connection when it's done to manufacturer specs.

I think the ends were tinned, though I am not sure. e used a LOT of solder pots

The plant I was stationed at made switches, relays, solenoids (by the millions). We had everything from 30-40 year old very manual production lines to automated lines similar to basic semiconductor assembly and single-layer boards. Wave soldering, parts placement etc.

Everything from starter solenoids first used in '55 Fords, to current at the time fuse blocks that were total automated assembly.

 

[mmckenna]

I think the ends were tinned, though I am not sure. e used a LOT of solder pots

Yeah, that's the way to do it. Someone doing it at home with a blowtorch and a roll of solder usually doesn't work out so well.

If you do a search on "Gas Tight Crimp Connections", you'll see what I'm talking about. A crimp connection done with the right crimp/tool and all designed for the conductor in use will result in a very good connection. We use them at work for high power DC connections, and they don't fail. It does require more than the $8.00 Wal*Mart crimp tool, though.

 

[wm8s]

I'm not completely sure, but reading the upfitter's guide, it looks like both of the ground straps that would let me go through the battery current sensor with my return are attached to the engine block and frame at the Seventh Gate of Hell [i.e., way down where I can't get to]. If I go straight to the negative battery terminal and bypass the sensor, is the only consequence that while I'm transmitting, the battery might charge a little less than it would if I were to return through the sensor? Or has anyone experienced BCM, sensor, diagnostic, etc., problems? If the former and I stick to one 50W radio, I'm not too worried about it. If the latter, I might have to find some change to give Charon....

...R

 

[mmckenna]

The current draw of your radio isn't the issue. It's that you are creating a circuit that bypasses the current sensor. The current sensor is needed to make sure the alternator puts out what is needed to keep the battery charged.

If you are only running a 15 amps worth of current draw, then just ground it to the body and let the existing wiring do the work. I know Ford allows up to 30 amps additional return current over the existing body to negative terminal connection.

The big issue is if you do things like add an amplifier or a lot of higher power transmitters. At that point, you'd want to upsize the return path through the hall effect sensor and to the battery negative.

 

[wm8s]

It sounds like the current draw of the radio is the issue, then: i.e., the BCM isn't sensing that return current, so it feels free to drop the battery charging duty cycle, thus the battery won't stay charged if the radio draws too much for too long.

I think an HF amp is unlikely to happen, nevertheless I'll still try to find a decent frame ground that doesn't require a floor lift. Thanks.

...R