Electrical smell from Genset

[diver dave]

110 in-lbs. Don't guess, that's what happened last time!


https://www.bluesea.com/products/5005/ANL_Fuse_Block_with_Insulating_Cover_-_35_to_300A

 

[AlanT]

Nice job tracking this down, and an excellent reminder to never ignore something that isn't right. This is the sort of thing that burns boats to the waterline.

+1

Also what a great advertisement for Trawler Forum. The herd got together and helped not only solve a problem, but possibly saved a boat!

~A

 

[catalinajack]

The surface does seem to make a difference in the reported temp, sometimes massively so. I think IR guns are good for comparative reading, but not so great for absolute temp measurement.

It’s also easy to get lured into thinking that you are measuring the dot when it can actually be measuring a large area around the dot. Best reading are at point blank range.

Twisted, yes, and here is my experience from several days ago. On a three hour run I went below to shoot the engines with a high quality Fluke IR gun. I hadn't done so in awhile. I take readings at the therostat housing painted flat black. I was initially horrified to see temps on both engines at around 285 degrees, highly unlikely in that neither 205-degree high temp alarm did not trigger, but frightening just the same. Then I remembered that my gun has an emissivity adjustment for shooting different surfaces. I adjusted from low to high and got readings of 163 degrees on both engines which are equipped with 160 degree thermostats.

 

[twistedtree]

Twisted, yes, and here is my experience from several days ago. On a three hour run I went below to shoot the engines with a high quality Fluke IR gun. I hadn't done so in awhile. I take readings at the therostat housing painted flat black. I was initially horrified to see temps on both engines at around 285 degrees, highly unlikely in that neither 205-degree high temp alarm did not trigger, but frightening just the same. Then I remembered that my gun has an emissivity adjustment for shooting different surfaces. I adjusted from low to high and got readings of 163 degrees on both engines which are equipped with 160 degree thermostats.

My cheaper guns don't have any adjustment for the surface emissivity - at least not that I have found. It really makes me wonder whether these temp guns are a net benefit or net liability given how easily they can misread a temperature. I guess the problem lies in how they appear so easy to use, when they are actually easier to misuse.

 

[diver dave]

https://www.tnp-instruments.com/sitebuildercontent/sitebuilderfiles/Infrared%20Thermometer%20and%20Emissivity.pdf

Yeah, there is a lot of "fine print" with the HH IR temp. units.
Like: hold the unit within 30 deg of true normal
avoid being near much cooler or hotter objects.
Pick the correct wavelenght sensor.
Adjust for the correct emissivity.
And, you don't think the unit only looks at the little laser dot for the active field, do you??

So, the cheap units give you a reading, but as noted, can be wildly off and not good enough for even our low tech job of engine temperature. I would easily trade dynamic range for much more useful features. I don't need to measure 1100 degrees....

 

[Juliet 15]

I think even the cheap ones can be helpful in that over time they provide a base line reading. I don't know of the 7 things I check hourly are exactly at the temps mine shows, but if it's different than it's always been that raises a flag for me. Additionally, the significance of the difference helps determine how critical any action needed might be.

 

[twistedtree]

I think even the cheap ones can be helpful in that over time they provide a base line reading. I don't know of the 7 things I check hourly are exactly at the temps mine shows, but if it's different than it's always been that raises a flag for me. Additionally, the significance of the difference helps determine how critical any action needed might be.

I think that's the best way to use them. You just need to be consistent in where and from what distance you take your readings. But I agree that in the end you are looking for things that have deviated from normal, and they are good at showing that.

 

[Kit_L]

What a great thread; thanks everyone. Electrical smells must always be investigated immediately, as others have said. And alongside good 7 x 50 binoculars, an IR thermometer is the other most important bit of gear aboard, I believe. And I did not know about specific torque readings for electrical connections (I have always done this by hand, and based on material being torques, and size of thread) but I shall update this approach!

 

[Comodave]

I used to work with a guy that believed in tightening up until it strips and then back it off a quarter turn…. Hated to work behind him.

 

[slowgoesit]

I used to work with a guy that believed in tightening up until it strips and then back it off a quarter turn…. Hated to work behind him.

That's not how you're supposed to do it?!?

 

[kiwi Brent]

I always crimp then solder cable to lug on marine cables

 

[boomerang]

I always crimp then solder cable to lug on marine cables

My goodness man! Do you know what just you've done??? You've just opened yourself up to being inundated with ABYC rules & regulations & quotes from pundits around the globe!
Classic rookie mistake

 

[kiwi Brent]

When I did my trade (Armature winder) in the early 70s You crimped to hold solder to connect and seal . 50 years of doing this and no failures. so people can say what they want.Rookie
The Shop I did my time in Had a crucible of solder molten you crimped lug to cable then lug into solder to heat take out a little resin flux back into solder a perfect connection every time (i have made my own crucible for electrical and motor cycle throttle and clutch cables etc

 

[diver dave]

I always crimp then solder cable to lug on marine cables

Put your lugs on a vib table. Report ur findings[emoji41]

NASA demanded a tool called “anti-wicking” pliers on soldered connections. This prevented molten solder from migrating outward inside the strands. The end of the solder filled stranded wire is a sudden solid to stranded transition that concentrates stress fatigue, causing failures at that point.

 

[boomerang]

No, I don't need your work credentials. I was just funning with you. By rookie mistake, I was referring to making the statement on the forum that you crimp & solder. Your small amount of posts was where the rookie remark came from. No harm was intended!
FYI, That's the only way I used to make large gauge connections , crimping & soldering. I've never seen one of mine or anyone else's fail when done correctly. Now I just crimp & they seem to do fine like that.
I've been in the business for a few years ,too.

 

[kiwi Brent]

Nasa went to the moon in the sixties when what is now called old methods of tradesmen were used.
cut open a crimped connection and you can see why they can fail in high current situations
Old is best
My 59 skyliner roof still opens and closes

 

[diver dave]

When I did my trade (Armature winder) in the early 70s You crimped to hold solder to connect and seal . ….

Using solid magnet wire, I suppose?