Blue Seas 125A t-fuse....stud torque really 3/8" pounds? Finger tight only?

[AlaskanNoob]

I'm trying to put my t-fuses in the t-fuse holder and if I'm reading this spec sheet correctly, I'm supposed to only torque the t-fuse to .34NM? My torque wrench min torque is 60 inch pounds, so if this is really the number I'm going to have to figure something out. That number seems so low. Seems to be finger tight which just seems odd, but I have no experience with such things.

Fuse A3T / Class T 125 Amp - Blue Sea Systems

Use with Class T Fuse Blocks for circuit protection of devices including inverters. high interrupt capacity for large battery banks including Lithium-ion and TPPL batteries.

www.bluesea.com

Stud Torque

3/8" in-lb (0.34 Nm)

 

[wheelman55]

Click on the “Works With”. The fuse holder listed there has much higher torque.

Where are you seeing that light torque number?

 

[AlaskanNoob]

Click on the “Works With”. The fuse holder listed there has much higher torque.

Where are you seeing that light torque number?

Yeah, the fuse holder has a higher torque but I wasn't sure if I was supposed to use that torque for the fuse holder studs that mount the fuse, or use the torque specified by the fuse itself. The 3/8" pound number for the fuse is on the fuse spec sheet:

Fuse A3T / Class T 125 Amp - Blue Sea Systems

 

[wheelman55]

Looks like a call to Bluesea is in your future

 

[AlaskanNoob]

Looks like a call to Bluesea is in your future

So annoying to not have such a basic item clearly spelled out.

 

[windsurfer]

Oh, its clearly spelled out... its just wrong

 

[AlaskanNoob]

Well, I'm just going to tighten the fuse in the fuse holder using the fuse holder torque and see what happens as I try to charge the battery for the first time.

 

[LydMekk]

I have the 225A version of the fuses. Torqueing mine to 14nm.

 

[AlaskanNoob]

I have the 225A version of the fuses. Torqueing mine to 14nm.

Thanks for the sanity check!

 

[Hedges]

And what exactly is "Stud size 190"

 

[Hedges]

These two differ a bit:

Fuse A3T / Class T 125 Amp - Blue Sea Systems

Use with Class T Fuse Blocks for circuit protection of devices including inverters. high interrupt capacity for large battery banks including Lithium-ion and TPPL batteries.

www.bluesea.com

Fuse A3T / Class T 150 Amp - Blue Sea Systems

Use with Class T Fuse Blocks for circuit protection of devices including inverters. high interrupt capacity for large battery banks including Lithium-ion and TPPL batteries.

www.bluesea.com

I would blame it on software. As I usually do.

 

[AlaskanNoob]

And what exactly is "Stud size 190"

The wife and I were just asking the same question. No units. What does that mean?

 

[AlaskanNoob]

We used the torque setting for the fuse holder and my first Pylontech is happily charging up. Fuse hasn't blown so all is well I suppose. I sent an email to Blue Seas to see what's up with that page.

Feels good to finally, finally, turn on a Pylontech and watch it charge up.

 

[Hedges]

For what it's worth, this bolt torque chart says 15 foot-pounds for 3/8" galvanized bolt. That would be 180 inch pounds.

Bolt Torque Chart - Portland Bolt

Torque values for various grades and diameters of fasteners.

www.portlandbolt.com

This one, 236 or 247 inch points for 3/8"-16 stainless alloys.

Torque Values Stainless Steel Bolt Table Chart

The following torque values are the maximums for for Stainless Steel and Nonferrous Fasteners based upon actual lab testing on clean and dry or near dry fasteners. For other friction conditions, significant modifications may be required.

www.engineersedge.com

 

[Oldphile]

0.34 Nm = 3 in-lb. Just convert the metric number.

 

[Tomthumb62]

Yet another thread where common sense would tell you that the listed number is wrong. And there’s multiple torque wrench threads where common sense would tell a person that the torque wrench they’re using isn’t trustworthy.

For electrical connections I’m having a hard time understanding the value of using a well calibrated torque wrench, assuming you have values that are actually correct. What’s so wrong about going by feel?

 

[windsurfer]

If you just go by feel, you will never get it correct and if it loosens up it will get hot and can cause a fire.

If you use a torque wrench you will at least think it is correct ?

 

[Quattrohead]

Common sense and feel are great.....until you get into aluminum and plastic parts, especially mixing in steel nuts and bolts.
But hey that's the difference between DIY and professional.

 

[Hedges]

For electrical connections I’m having a hard time understanding the value of using a well calibrated torque wrench, assuming you have values that are actually correct. What’s so wrong about going by feel?

Inspecting Electrical Connections for Proper Torque

iaeimagazine.org

 

[Tomthumb62]

If you just go by feel, you will never get it correct and if it loosens up it will get hot and can cause a fire.

If you use a torque wrench you will at least think it is correct ?

If it loosens up because you went by feel then you need you recalibrate your sense of feel.

If you think it’s correct because you used a (out of true) torque wrench, then I would not want to sleep in your house lol.

Can you tell I don’t trust most torque wrenches? Most people only think their torque wrench is calibrated but have never done so nor even know how to.