Black Friday Ambo

[flightcancled]

More things to help anyone that may follow.

Been on emergency work for days, but managed to squeak in a bit of time to get the flashers circuit out and repurpose the flashers to floods.

Before:

After:

Things to note:

This has a BIG draw once all the lights are on at once.

The flasher is ground switched so if you are nuts like me you have to flip the signal wires to the relay and give the switch power from the master in order for the illumination on a normal toggle switch to work.

With that I am out of things that need to get done to wrap up my wiring conversion/ updating and board transplant. Now to just finish the box. Test fit and shakedown in the ambo went well so it's just a matter of having time again.


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[Mountainunicycler]

So I may be missing something, but what did you mount the little step rungs into? I'm assuming you went through the skin and into a support, but how did you find the support to bolt to?

They look really useful and way better / cheaper than the ladders I've been thinking about because there's no good place for a ladder.

Edit: Now I see how you did that I have a different question; did it all go back together?

(Also I agree with the part about the medtech engineers being evil geniuses)

 

[flightcancled]

Exposed a support where I didn't have to put things back flush against it. Drilled through the top and bottom from the inside. Measured the distance the bolt had to travel through the wall so I could find the shortest length possible without cutting off the bolts later. Ran a string on the outside. Installed the top and bottom steps. Calculated the center to center distance for the remaining steps and installed.

It was a bit of a pain(wiggling things back in, not because of the bolt heads), but yes it is back together with the exception of the cabinet which will stay off until I have the roof D-rings bolted.

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[Mountainunicycler]

Thanks, it's super helpful to see another medtech taken apart since I worry I can't afford to re-fabricate things at the moment.

 

[flightcancled]

Anything you run across just ask. I've spent untold hours just trying to figure out what they did before destroying something and not being able to put it back. Hopefully that can all go towards helping someone else.

I also have some of the aluminum trim squirreled away I MIGHT be willing to part with if you get in a jam. It's awesome for covering your tracks!


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[flightcancled]

Work has been insane, but I at least have time to work on things mentally driving... Woo

I'm getting really sick of my power issues with starting the ambulance. I thought putting brand new marine grade batteries in would be a game changer but that has not panned out. I do think it is VERY likely the battery isolater which was pointed out earlier causing my issues.

I have never gotton a reading above 13.5 on my volt meter, and it quickly drops if I am using lights once the engine is off. If I have messed with something or left the rig sitting my low battery light comes on in the display and I have to crank it over a few times to start the engine. If I force the engine over without waiting for the glow plugs the engine can be stalled out by the plugs continuing to cycle once it starts.

To me this all points to the fact that the system was built to be plugged in 24/7 waiting to be started, which just isn't how it will live the rest of its life. Unless there is a larger issue I think I need to make a change to something which wont have a power drop and acutally give me a full charge.

A quick search has given me this bit of info from another board:

I used to have a former NYC EMS ambulance (Chevy C30) as a work truck, and I completely re-wired everything from batteries to emergency lighting and here is what I did with the batteries...

The ambulance came with worn out dual batteries along with dual 300amp constant duty solenoids, and a dual output battery isolator...

I purchased a 900 cold cranking amp battery for starting the truck, and an Optima yellow top deep cycle for the vast lighting and existing external PA system (awesome for venting road rage by the way...) I chose to add a third battery, (this time a LARGE one that they put in semi rigs) and place that within one of the bays of the ambulance body - This one was to power the extensive A/V system that I had planned for back there... I then swapped the dual output isolator for a three output model to accommodate the extra battery.

The starter battery was wired directly to the starter and nothing else, save for the isolator for charging it (I figured I could manually use jumper cables to one of the other batteries in the rare occurrence that my starting battery was dead - that never happened).

The lighting deep cycle battery was wired to one of the solenoids so that I had a remote switch in the center control console to kill all lighting power when I parked somewhere (there was a TON of lights on this thing and wanted to make sure that everything was off with one switch). I even ran a bunch of relays to a trigger switch so that with a single flip I could change the lights from my custom use controls (extra flood lights, extra tail lights, grill guard mounted flood and spot lights) back to the original emergency flashing controls within the center console.

The semi battery was wired through the second solenoid so I could kill the A/V system juice when I wanted to make sure that it was off as well.

About the time I got all these modifications done, gas jumped over $2 a gallon, so I stopped driving it, and got rid of it a few years later...it got 8 miles to the gallon...yes, 8 (at $2 a gallon it cost me $40 to drive it 100 miles)...and that was double what it got before I upgraded to a header/dual exhaust system with AeroTurbine mufflers with 3" pipes...LOUD!!!

I do not think this was useful to you at all, but felt the need to share the story of my shrine to automotive wiring overkill...did I mention all this battery wiring was done with 2/0 welding wire...?

I would say that you should definitely plan on using a battery isolator if you are planning on dual batteries. If you think you will be draining one more than the other for some reason (big sound system or power inverter while the engine is turned off), choose one battery for that purpose, and leave the other dedicated for starting the truck, and every other OEM power need. As long as you buy quality batteries designed for each purpose you should never have a need to tie both batteries together.

If you require additional "run time" for the system that draws a bunch of power while the engine is off, then plan on buying an additional battery(s), and wire them in parallel to the battery designated for this purpose. Your isolator will still work the same - independently charging both the starting battery, and the "accessory" battery bank...

I feel that the only time a solenoid would be a good idea is if you required a remotely controlled "kill" switch for either of these applications. I liked the peace of mind of "killing" juice to all of those 2/0, high-amp, long length cables when I was not around. Plus, I was worried that the gear reduction starter for the 454 big block would pull than 300amps (what the solenoid was rated for) when I tried to start the ambulance in the winter - so I did not run this short power run through a solenoid.

I guess you could use a solenoid to remotely tie two batteries in parallel, but it seems like a significant expense over what a good high amp starting battery would cost - just keep all of your high-power draw accessories wired to the other battery.

Also, keep in mind that if you tie both isolated batteries together, you are defeating the purpose of the isolator, and I am unsure how the isolator (or the alternator for that matter) would react to this output connection once the engine starts.

link: http://www.toyota-4runner.org/933841-post7.html

This totally contradicts what I saw in the donor ambulance I pulled apart. There was NO isloater in the charging system at all. One alternater went directly back to the house batteries, and another linked directly to both of the cab batteries. Pat can fill in what was going on on the distribution end, but it was totally down and dirty.

Now those were matched batteries. I have a smaller marine grade starting battery, and a size 27 marine deep cycle. While together there should be more than enough amps to easily throw the engine around, because they aren't matched it does appear I need some way to seperate them. This has me liking the advice from above- except I really want to toss anything that will continue to rob my power. The simple answer appears to be to dedicate one alternator to the starter and the other to the cab marine grade battery and the future house battery bank, however that would mean really cranking on the second alternator.

 

[polksfinest]

You need to get rid of the marine starting battery's and just get 2 group 31 if they fit or what ever fits but they must be regular starting batterys the marine battery's don't have the starting capacity that a regular battery does if you are going to use the battery isolator then use it between the starting battery's and house battery's
My ambulance has one wire off of the starting battery's straight to the starter and one wire from the starter to the main sol which has the other battery hooked to it so in essence they are tied together when the key switch is on or battery shut off is on


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[Mountainunicycler]

It sounds like my power system is a bit simpler, just two batteries under the hood and then a selector on the seat, but what I did was replace the mostly dead originals with these:

They were expensive but they're supposed to last through the deep cycle use pattern and still provide the 900+ (I don't remember exactly how much) cold cranking amps to start the engine.

I've only had them in for a few hours but I really hope they'll be the solution to not having to have separate starting batteries and house batteries.

 

[patoz]

Alex,

Electronic battery isolators are inefficient at best, especially if it's an older model. They require constant power when they are in use, and will not allow your batteries to come up to a full charge. My advice is to get rid of it and go with a system using an Automatic Charging Relay. Just make sure you get the proper Amp rating for your alternator and load.

I sent you some of this information before, but take a look at this:

Battery Isolators are made with two or more silicon diodes that act like check valves. The diodes will pass current from the charging source to the batteries, but will not pass current backward from one battery to the other or back to the charging source. Nature extracts a price for this by causing a voltage drop of about 0.7 Volts across the diodes. If you have a regulated charging source that senses its own output, the voltage at the battery will be lower than at the charger or regulator and, if not compensated for, will lead to inadequate charging.

ACRs or Automatic Charging Relays are automatic switches that close when the voltage on one of the batteries rises to a level (normally 13.2V to 13.7V) indicating the battery is connected to a charge source and is partially or fully charged. The switch then closes and shares the charging current with the other battery until the voltage drops to some lower level (normally 12.4 to 13.1 depending on model) and the switch opens. This prevents discharging both batteries when there is not enough current to charge both batteries.

Read the rest: http://www.bluesea.com/resources/58/Battery_Isolators_and_Automatic_Charging_Relays


Automatic Charging Relays - ML-ACRs
http://www.bluesea.com/products/category/Automatic_Charging_Relays/ML-ACRs

Manual Battery Management and ACR SubSystem
http://www.bluesea.com/systems/39/Manual_Battery_Management_and_ACR_SubSystem

ML-ACR (Automatic Charging Relay) and ML-RBS (Remote Battery Switch)
http://www.bluesea.com/systems/37/Remote_Battery_Management_and_ACR_SubSystem

This stuff is expensive, and I know you're trying to keep the cost down, but how much is an off-road recovery or jump start going to cost at night afterhours in a freezing rain storm? Just something to think about.

 

[cjken]

About the floods. Do you now have 4 floods on each side??
Are all of the repurposed floods / flashers on one switch?
I'm repurposing my flashers as well including two on the front light bar which now has clear lenses on the Ends.
My original floods can be turned on individually rt side, left side, rear. What about connecting the repurposed flashers to the existing flood circuits?
And then adding a new relay and switch for the fronts?

 

[cjken]

Here are the ends of my repurposed light bar

 

[flightcancled]

Pat thank you so much for the info (and patience!) but I'll have to look at that once I catch up on sleep and have my full mental functions back. I had only 5 min a few days ago to myself so I ripped the driver seat off the base and took some photos but I haven't even looked at them yet.

If I recall correctly there is a copper bus in the engine compartment where the cables from the alternator meet and then come to the alternator pin on the isolator. It's probably my state of mine but I am baffled as to how I'm doing the wiring at the moment.

Ken- the outside sets of lights (closest to the front and rear were the flashers and the inside were the floods. I've left it that way. So I can now select to turn a set of lights on to look right or left, or flip the "flashers" on to light up the entire perimeter.

You could totally connect them all as one, but I have all these switches to play with and the power draw outweighs the benefit at the moment.

Lights are looking sweet! Definitely makes me want to get on supercharging my front facing "flashers" and tie them into the front light bar switch as offroad lights.

My coworker will be bringing the steps down Thursday. I'll give him your number. Should be around for most of the morning then he has to go to NJ.


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[cjken]

That is great!!
I'll make sure that I am available Thursday morning.

Yes I agree about power consumption. I will probably run 1 switch for both sides of outer repurposed lights and leave the controls for the current floods alone.
Then have a separate switch to turn on the repurposed front light bar.
The ambos are definitely not wired with efficiency in mind.
I plan to add two house batteries to the box and use a manual switch to separate the two systems. At least for now.
I was able to pull several long heavy power cables from the donor ambulance.
Making some progress just slowly.
Thanks so much for arranging the step drop off
Let me know what dash pieces you want. I'll let you know what kind of shape they are in. The donor ambo is a bit rough in the cab but there are probably some good pieces

 

[patoz]

Alex, after looking at those pictures I thought of something else. What if the isolator itself was bad, or only partially functional, and was preventing both batteries from getting the maximum charge it's supposed to provide?

You may be able to tell by using a volt meter and testing at the isolator terminals for voltage with (1) engine off (baseline), (2) engine at idle, (3) engine running with a load (lights on) and high idle activated. Connect the Black lead of the meter to ground, and use the red lead to check at each terminal and compare the readings. After you do the test with the engine running and a load, you may have to wait 10 minutes or so to give the batteries a chance to charge, and do another test.

Hopefully, that will give you some kind of profile to go by.

 

[tgreening]

First thing to come to mind after looking at those pictures was "Electric Chair". Old Sparky lives again! I'd be extra careful with my Mega Jumbo Slushy. Hate to cause a short of that magnitude right under MY butt.