power for multiple radio install

[medicnurse]

I have a three radios to install
Motorola xtl 5000 uhf
Motorola Mcs 2000 vhf
Icom 208H
and I want to be able to turn them off and on with the key I currently have a 4 gauge hot wire coming in to the truck and into a fuse block for the current setup . I would like to have some way to turn off the radios when the truck is off. I also have a 7 circuit boss from painless products but have not installed it because the 2 motorola radios both have a 10 gauge wire for power and the power for the entire block only has a 10 gauge wire. NEED HELP!!!

[crazyboy]

I'm not sure about the icom but the other 2 radios only need switched power on their accessory wire. Place a fuse tap in the vehicles fuse panel on a circuit that goes on and off with the key, I prefer the audio circuit. You could probably get away with connecting the ignition sense wires straight to that since they draw such little power, but if the Icom doesn't have an ignition sense wire then you are going to have to use a relay.

[Jim202]

The trick here is to consider how many transmitters will be keyed at the same time. This is your total current draw
and as such is what determines what size wire is needed to feed the circuit boss. If it was me, I wouldn't worry
about it. I can only hold one mic at a time and still stay on the road.

Jim

I have a three radios to install
Motorola xtl 5000 uhf
Motorola Mcs 2000 vhf
Icom 208H
and I want to be able to turn them off and on with the key I currently have a 4 gauge hot wire coming in to the truck and into a fuse block for the current setup . I would like to have some way to turn off the radios when the truck is off. I also have a 7 circuit boss from painless products but have not installed it because the 2 motorola radios both have a 10 gauge wire for power and the power for the entire block only has a 10 gauge wire. NEED HELP!!!

[kf4sqb]

The first two to reply both have valid points, but to simplify, put it all on a relay. The quickest, most reliable way to do this: Go to your local parts store, hope you get a semi-intelligent person behind the counter, and tell them you want an old-style Ford starter solenoid. A switched circuit from the ignition shouldn't have any problem picking it up, and the contacts are good for at least a couple of hundred amps. Overkill, but they're cheap, and you know you won't have a problem with it for some time. Some parts stores will also have an "accessory fuse panel", that takes "blade-type" fuses, and have a screw-terminal for power feed. Most that I've seen have a number 10 stud for the power feed, male spade terminals for power output, and 6 or 8 circuits, each with it's own fuse. Between both components, you have lots of room for future additions.

[arlojanis]

Starter solenoids are not rated for continuous duty and many will over heat if left keyed for long peroids of time.

[kf4sqb]

Starter solenoids are not rated for continuous duty and many will over heat if left keyed for long peroids of time.

One of the trucks at a volunteer FD I'm a member of has a pair used for battery switching. Perhaps the people at Ward LaFrance aren't aware they aren't usable for continous duty? Did I mention that the same pair of solenoids has been in use on this truck since the early 80's?

[FireCpt809]

We use a 75 amp relay for things of that nature. In the 12 yrs of installing public safety equipment I have yet to install a selenoid.

[tvsjr]

Starter solenoids are not rated for continuous duty and many will over heat if left keyed for long peroids of time.

The problem with blanket statements... you can usually find a case where they're wrong. There is such a thing as a continuous-duty solenoid - you could also parallel Bosch 75A relays to reach whatever current capacity you'd like.

[kb9suy]

running the 4 gage wire to the fuse panel is fine. mcs2000 and xtl to the fuse panel. a 30amp relay for the icom radio with main power tied to fuse panel. Now you have to find a igition lead to tap into for turning the relay and two radios ignition wires. I can't tell you were to tap into unless I know what type of truck and year. usually the car radio or cigarette lighter are a good spot if their setup for ignition. You can use the fuse style tap that plug into the fuse box and have a small lead that comes of to connect a wire and put the original fuse back in for said circuit and anothe fuse for the ignition lead. Or a t-tap fused of the feed wire. I don't believe you need to put all the radios on a relay for their main power unless you run into the radio draining the battery. Remember to fuse the main 4 gage wire at the battery. I recommend a fast blow resetable circuit breaker remember to add up the amps and add 35% over that, so fuse for 135% of the equipment. that allows for build up of heat. Any question feel free to pm.

[medicnurse]

Thank you for all the help. I am still a little confused with the relay how to wire it and where it hooks into the fuse block. Right now I have a 4 gauge wire coming off the battery and into a 100amp circuit breaker and then to the fuse block. I am currently turning the radios on and off as needed. However, i also have a cell phone amp that drained the battery and had to be replaced. the battery was 5 years old. Currently have cdm1250, yeasu 8900, 200watt whelen siren, 2leds, 90watt strobe power supply and the cell phone amp coming off this fuse panel. I am going to chance the strobes for leds when I get the money.

[crazyboy]

Here, Not sure whether all the lines are going to confuse you, I went overboard

[tvsjr]

Thank you for all the help. I am still a little confused with the relay how to wire it and where it hooks into the fuse block. Right now I have a 4 gauge wire coming off the battery and into a 100amp circuit breaker and then to the fuse block. I am currently turning the radios on and off as needed. However, i also have a cell phone amp that drained the battery and had to be replaced. the battery was 5 years old. Currently have cdm1250, yeasu 8900, 200watt whelen siren, 2leds, 90watt strobe power supply and the cell phone amp coming off this fuse panel. I am going to chance the strobes for leds when I get the money.

Let me make a couple of suggestions:
1 - Ignore Crazyboy's diagram - I don't know what that's designed to do besides totally confuse someone.
2 - Find someone knowledgeable in your area who's willing to help you. What you seek to do is not very difficult. You'll save yourself some headaches by seeking the help of a local friend or acquaintance - especially if your first attempt is improperly wired.

[SlimBob]

Starter solenoids are not rated for continuous duty and many will over heat if left keyed for long peroids of time.

The problem with blanket statements... you can usually find a case where they're wrong. There is such a thing as a continuous-duty solenoid - you could also parallel Bosch 75A relays to reach whatever current capacity you'd like.

IIRC a solenoid is a rod of metal sticking out of a coil that either moves in or out when current is applied. A contactor, however, is a f***ing large relay.

http://en.wikipedia.org/wiki/Solenoid

http://en.wikipedia.org/wiki/Contactor

And they do make contactors in unreasonably large sizes and ratings.

[SlimBob]

However, i also have a cell phone amp that drained the battery and had to be replaced. the battery was 5 years old.

Check with the guys at the Auto Parts store; most batteries are not guaranteed or warrantied longer than three to five years. Five years is about par for the lifetime of a car battery.

Thank you for all the help. I am still a little confused with the relay how to wire it and where it hooks into the fuse block. Right now I have a 4 gauge wire coming off the battery and into a 100amp circuit breaker and then to the fuse block. I am currently turning the radios on and off as needed. Currently have cdm1250, yeasu 8900, 200watt whelen siren, 2leds, 90watt strobe power supply and the cell phone amp coming off this fuse panel. I am going to chance the strobes for leds when I get the money.

I would switch to 2GA wire to be safe. 4GA wire will handle 90A, but it will be a lot closer to 200 degrees than you'd normally want it to be.

[james04tj]

You are off to a very good start. As the first reply that you received indicated, you will want to use the accessory lead on the Motorola rigs to provide ignition sensing. You can pull this from any power source that is controlled by the ignition. For the Icom all that you need is a 20 amp relay that you can get at any electronics or automotive store. In an automotive store you will find them either in the electrical isle or the isle with aftermarket fog lights. It should cost around $3.00. The relay will have 4 or 5 blades on it and there should be a schematic on the package or the relay itself. One will go to the fuse panel that you have installed, one to the radio's 12VDC+ lead, one to ground, and one to the source that you have identified for ignition power.

One location to pull easy ignition power from is the cigar lighter wiring if it is switched with the ignition. Another would be from the wiring harness to the stereo. Both the ignition sense wires on the Motorola accessory connectors as well as the relay will pull such a small amount of current that either is an acceptable source.

[fineshot1]

Perhaps one of these will do the job for the main power buss feed?

http://www.acdcind.com/mzl100.php

Then route the ouput of this to a distribution block of your choice.

However - if the XTL5000 is being used on a trunk system I would wire that
up seperately due to when ignition is killed it needs to de-affilliate with the
trunk system and if you kill main power to the chasis it will not have the
chance to do that.

Added benefit of the MZL100 is that the timer will later kill main power to
all of the equipment eliminating the chance of any vehicle battery drain.
Timer can be set to almost any reasonable delay before power is killed.

[ab]

medicnurse, back to your question........

Find an Acc. switched power for the two motorola radios, see hookup in Moto. manual or ask here,

Hook up them up with their fused leads and another fused wire to a relay (Bosch 75A are a very good choice) to control the Icom.

Another reason to use the wires on Motorola radios so if they are progammed for home mode
they will stay on the same channel/mode when you turn key back on.
Your Icom will depend on model.