Big Blue's HVAC Blower Issues

[ArdWrknTrk]

I'm sorry, I don't know.
I know they have a huge selection, and this is where I got my silver contact starter relay.... back when I actually use the fender relay.

They also have a wide selection of battery isolators and all the industrial Cole-Hersee and White-Rodgers controls

You should really have a look at their whole catalog

[Gary Lewis]

Yes, I do see that they have a very wide range of products.  They even have the Cole-Hersee 48530 battery isolator that I'm using on Big Blue.  And other products I've never even heard of.  

And, they may well be right about the Bosch 0 332 019 103 relay being a 50A unit, in spite of what this "Bosch catalog" says.  I'd forgotten that we have a Bosch catalog on the site (Documentation/Electrical/Relays & the Bosch Relays tab), and that catalog says that the 0 332 019 103 is indeed a 50A unit, as you can see below.

And that page shows the contact voltage drop, both new and "after life", whatever that is.  At 12V & 10A those are .05v and .08v respectively.  In fact, if you were to scroll on down in that catalog you'd find that the 30A & 40A-rated standard relays have the same voltage drop specs at 10A.

So I must be doing something wrong in my testing since I'm seeing .3 to .7V drop, which is about 10 times more.  I guess my wiring might make up part of that, but I wouldn't think it would account for all of it - especially on the relays that had more drop.

Given that I'm trying to come up with better testing approaches and would welcome input.  For instance, I've been pulling the relays in and then applying the load.  Maybe I need to make the relay switch the load?

Thoughts?

[Ifitaintbroke]

Bill, where did you find that? That's one of the funniest things ive ever seen!
Sadly it's true.

[ArdWrknTrk]

#1 rule of any kind of electronics.
Don't let the smoke out!  

This valuable Lucas product is very rare today, but back in the days of Leland, Healey, Triumph/BSA/Norton it was a shop essential.

[Gary Lewis]

Yes, it is true.  Been there and done that.  But have now run out of refills.

But back on the relay quest, I'm quite confused.  I've found lots of people selling the Bosch 0-332-019-103 relay, which Bosch's catalog says is a 50 amp unit, but some list it at 50A, some at 40A, and some at 30A.  And yet, when a picture is provided it is the same relay.

All I can think is that the people that created the listings either don't know what they are doing or looked at the Bosch catalog and saw that the thing is rated for a different number of cycles depending on the current being handled and used the one they thought best.

So I'm thinking of ordering some in today, which is why I asked Copilot to find the best prices on it.  But Copilot doesn't seem to know how to account for shipping, so where it found the relay for $5, at Pelican, the shipping is $5 and it'll be here in a few days.  Or I could pay $6 for the relay and $13 for shipping at CarParts.com and it'll be here some time next week.  But Copilot didn't list Amazon, which has the relay for $10/ea and free shipping - and it'll be here today.

As for Texas Industrial it won't let me order that relay.  There's no link to add it to the cart nor a buy-now.  It says "Please Specify if you need 12-10 ga Terminals", which I don't understand.

May call Texas and see.

[ArdWrknTrk]

10 ga. terminals are the wider ones you don't like (but they're rated for 40A)
TIE offers the same exact relay with smaller spades, which is probably what you're finding on Amazon... or whatever.

[Gary Lewis]

Thanks, Jim.  That makes sense.  I sure don't want the larger terminals.  But it is interesting that I don't see different terminal sizes in the Bosch catalog.  

Which gets me back to my testing methodology.  Perhaps it isn't the relay that has the voltage drop but the terminals or wiring in the PDB.  So I'm planning on making up some jumpers today to test the relays outside of the PDB.  Then I can measure the voltage drop of each device/connection.

[Gary Lewis]

Called TIE and talked to Steve.  Told him I'm interested in the Bosch 0 332 019 103 but don't understand the bit about their request to "Please Specify if you need 12-10 ga terminals".  He said that all of those relays come with the same standard-sized terminals.  But that the majority of existing equipment out there has terminals that are only good for 28 - 30 amps.  So if you are going to use the full 50A capability of the relay you'll need a socket they have which has much better terminals.

Then I asked how to order 'cause I don't see a way to do it.  He said that's their plan - you order from him, which has resulted in essentially zero returns over the years.  So I ordered two of those relays.  

Now I'm working on a way to test relays in the blower circuit and see where I'm dropping voltage...

[ArdWrknTrk]

I think we need another player in the vendors reviews.

They're obviously doing it right and care that their customers get the right part(s) the first time!  

[Gary Lewis]

Good plan, Stan.  Go see what you think, and vote: https://forum.garysgaragemahal.com/Texas-Industrial-Electric-Company-td144903.html  (Not sure who's already voted.  )

As for what I did, I did a bit of playing with jumpers and tested the Motorcraft relay in the PDB.  Now, with better jumpers, I have the voltage drop down to .25 instead of the .31 to .35 previously reported.  So the jumpers and connectors are critical in measuring this.

Hopefully tomorrow I'll get a setup where I can test the relays themselves and see if I can tell where the voltage drop is coming from.

[ArdWrknTrk]

Done!  

[grumpin]

Gary Lewis wrote

Called TIE and talked to Steve.  Told him I'm interested in the Bosch 0 332 019 103 but don't understand the bit about their request to "Please Specify if you need 12-10 ga terminals".  He said that all of those relays come with the same standard-sized terminals.  But that the majority of existing equipment out there has terminals that are only good for 28 - 30 amps.  So if you are going to use the full 50A capability of the relay you'll need a socket they have which has much better terminals.

Then I asked how to order 'cause I don't see a way to do it.  He said that's their plan - you order from him, which has resulted in essentially zero returns over the years.  So I ordered two of those relays.  

Now I'm working on a way to test relays in the blower circuit and see where I'm dropping voltage...

Impressive!

[Gary Lewis]

Got a note from TIE today and the two 50A relays are on their way.

Given that I thought it might be time for me to do the work in the PDB, so I pulled it loose and got to work.  That means I disconnected all the power feeds to the PDB, moved the coolant recovery/windshield washer reservoir to somewhere where it won't spill, removed the bracket that the reservoir & PDB bolt to, got the lower shield off the PDB, and started identifying wires.

But that's where things started getting "interesting".  First, I realized that I'd mis-connected the power wires to the PDB.  Instead of connecting the megafuse, batteries, and starter to the bus of the PDB and the alternator to the other side of the megafuse, as shown below, I'd swapped them.  So if the fuse had blown the vehicle would be running on the alternator, and if any of you have tried to do that you'll realize it doesn't work at all.  Instant shutoff.  So I'll just swap those wires when it goes back together.

Next I found that the fuse slot I'd planned to use was already in use - it powers the fender-mounted starter relay.  (That relay just pulls the PMGR starter in, and the main power to the starter comes from the PDB's bus.)  But the yoyo that did the wiring forgot to document that.  

But after that it was smooth sailing.  I've found the three wires to the blower power relay that I need to connect to - the fourth is already grounded as it should be.  And I found a length of the Br/O wire to use and opened up the harness to get to where I need to tap in.

But that'll have to wait until tomorrow as we have more errands to run this afternoon.  Hopefully I'll get the connections made and get to test it out tomorrow.

[ArdWrknTrk]

Progress is GOOD!!!   

[85lebaront2]

I agree with Jim, progress is good. Do you want to come document my konvertible wiring??

[Gary Lewis]

Thanks, guys. But I don’t think you want me as your documentarian. I’m finding I didn’t do a good job on my own truck.  😩

Tomorrow I hope to get the power relay wired and check out the ground relay to make sure I’m happy with the connections and wire size. And then power it up for a test.

[Gary Lewis]

Didn't get it all wired up.  Got sidetracked on the C610/3G discussion and then getting ready for the class I teach at church tonight as well as the trip tomorrow to Dallas get the blue captain's chairs.

But, I did get a bit done.  I soldered and heat-shrinked the Br/O wires into the feed from the fan switch to the blower motor just ahead of C603.  And I opened up the convolute running along the fender and started running those wires with the others that go there.  But then I realized that the guy that ran those wires was apparently anxious to get done and didn't really lay them in neatly, so I spent some time sorting that out.  

I think another day on this, maybe Friday, and I'll not only have it wired and tested but maybe put back together.  Or maybe I should say Saturday?  Still, I want to get this done so I can install the seats!

[Gary Lewis]

Got the wiring done, tested, and then everything tidied up.  Wow!  What a difference!  Now the next-to-top speed is about as fast as high used to be.  And high is MUCH better.

I did some testing and found these before & after readings on High:

Voltage @     Voltage @ Motor
Battery         Before         After
12.5V            7.9V          11.7V
13.7V            8.5V          12.9V

So to say the difference is MUCH better is an understatement.

[ArdWrknTrk]

It's almost like you need one of those little anemometer's....

[Gary Lewis]

Yes, that would be an interesting test.  But I'm going to leave it where it is as I've gotten a dramatic improvement, even though there's a bit left to be had if someone really wanted to pursue it.  That .8v drop is across several connectors, wires, relays, etc.  But it could be less if someone really wanted to work on it.

However, these #'s are with the new 50A relays, so it isn't likely the drop is across the relays themselves.  But it might well be across the relays' connectors since Steve pointed out that they carry a special socket they recommend if you are going to try to put 50A through those relays.  And then there are the connectors to the fuse.  So right there you are talking about 6 connectors, but then there's the "little" connector to the blower motor itself, which has smaller terminals than the relays or the fuse.

So I'm happy with the results I got.