Low amp 48v fuses?

[Fraser]

Hi everyone. I thought it was too good to be true I found a place that sold 48v mega fuses. Or did I....... So found a place online called altecautomotive. Their web site stated that they are 32vac and 80vdc. So I thought great! I sent the guy a message to make sure that was correct, and he said they would be fine for my 48 v system as they have a 80vdc rating. When the fuses arrived it says only 32v on them. I’m still not convinced they are right. What do the great minds of the forum think? cause I’m an untrusting type and a little worried. In short ..... help
Many thanks

Fraser

 

[Johncfii]

Can you post a link to the web site page with the description of the fuse?

 

[Hedges]

Searching for 80V and Mega, I find some fuses referred to as Mega but they look like MRBF.
I do find a variety of Mega fuses, some rated 32V and some rated 58V.
It seems they vary - can you determine a brand and model for the fuses you received, and look up their specs?

Fuses have varying "AIC" rating depending on the voltage. A fuse that can interrupt less than 1000A short circuit current at 58V would interrupt more current at 32V, but we can only have complete confidence if it was tested and spec'd that way.

Here's one data sheet that says 70 VDC

https://www.littelfuse.com/~/media/automotive/datasheets/fuses/passenger-car-and-commercial-vehicle/bolt-down-fuses/littelfuse_mega70v_sf51_datasheet.pdf

Your retailer's site says they have multiple brands

Genuine MTA, DURITE & LITTELFUSE Branded MEGA fuses <br>(40 - 500 Amp rating)

Please choose your requirements from the "RED BOX" Drop Down menu situated just above the "ADD TO CART" Tab.function

www.altecautomotive.co.uk

You might have to ask them to provide a data sheet that supports the voltage you need, and to fulfil the order with fuses of a brand/model meeting that spec. Likely once the order is placed, somebody just grabs one of the right current rating and nothing else.

A fuse should have amperage rating, voltage rating, and AIC rating suitable for the application. Also the right trip curve - don't know if those vary for Mega, but other fuses and breakers are do.

 

[Fraser]

Searching for 80V and Mega, I find some fuses referred to as Mega but they look like MRBF.
I do find a variety of Mega fuses, some rated 32V and some rated 58V.
It seems they vary - can you determine a brand and model for the fuses you received, and look up their specs?

Fuses have varying "AIC" rating depending on the voltage. A fuse that can interrupt less than 1000A short circuit current at 58V would interrupt more current at 32V, but we can only have complete confidence if it was tested and spec'd that way.

Here's one data sheet that says 70 VDC

https://www.littelfuse.com/~/media/automotive/datasheets/fuses/passenger-car-and-commercial-vehicle/bolt-down-fuses/littelfuse_mega70v_sf51_datasheet.pdf

Your retailer's site says they have multiple brands

Genuine MTA, DURITE & LITTELFUSE Branded MEGA fuses <br>(40 - 500 Amp rating)

Please choose your requirements from the "RED BOX" Drop Down menu situated just above the "ADD TO CART" Tab.function

www.altecautomotive.co.uk

You might have to ask them to provide a data sheet that supports the voltage you need, and to fulfil the order with fuses of a brand/model meeting that spec. Likely once the order is placed, somebody just grabs one of the right current rating and nothing else.

A fuse should have amperage rating, voltage rating, and AIC rating suitable for the application. Also the right trip curve - don't know if those vary for Mega, but other fuses and breakers are do.

I agree. Plus they arrive in a little plastic bag with no details. They just have their business card in the bag.

 

[Fraser]

Can you post a link to the web site page with the description of the fuse?

Can you post a link to the web site page with the description of the fuse?

don’t need to Hedges the photon sorcer has found it ?

 

[Fraser]

Searching for 80V and Mega, I find some fuses referred to as Mega but they look like MRBF.
I do find a variety of Mega fuses, some rated 32V and some rated 58V.
It seems they vary - can you determine a brand and model for the fuses you received, and look up their specs?

Fuses have varying "AIC" rating depending on the voltage. A fuse that can interrupt less than 1000A short circuit current at 58V would interrupt more current at 32V, but we can only have complete confidence if it was tested and spec'd that way.

Here's one data sheet that says 70 VDC

https://www.littelfuse.com/~/media/automotive/datasheets/fuses/passenger-car-and-commercial-vehicle/bolt-down-fuses/littelfuse_mega70v_sf51_datasheet.pdf

Your retailer's site says they have multiple brands

Genuine MTA, DURITE & LITTELFUSE Branded MEGA fuses <br>(40 - 500 Amp rating)

Please choose your requirements from the "RED BOX" Drop Down menu situated just above the "ADD TO CART" Tab.function

www.altecautomotive.co.uk

You might have to ask them to provide a data sheet that supports the voltage you need, and to fulfil the order with fuses of a brand/model meeting that spec. Likely once the order is placed, somebody just grabs one of the right current rating and nothing else.

A fuse should have amperage rating, voltage rating, and AIC rating suitable for the application. Also the right trip curve - don't know if those vary for Mega, but other fuses and breakers are do.

So far they have sent brand names ‘little fuse’ and ‘MIA’ I think that’s what it says. I will see if I can get a data sheet on them.

 

[Fraser]

So far they have sent brand names ‘little fuse’ and ‘MIA’ I think that’s what it says. I will see if I can get a data sheet on them.

Yeah them fuses they have sent all have to go back. It does annoy me when you even ask just to make sure they really are 80vdc. Just lazy incompetent people. So don’t bother with them. Not sure what I’m going to do about the 400 48v fuse. I have upped my wiring so 125 amp fuse will work on the rest of the system. But I can’t get a 400. I have spent more time looking at fuses than I have on the rest of the whole system.

 

[mike95490]

I like the midnight DC breakers. Rated for switch duty and 150VDC

 

[Fraser]

Yeah wishing I hadn’t git 2 lynx power inns as my distributors now.

 

[HRTKD]

I like the midnight DC breakers. Rated for switch duty and 150VDC

Agreed. They have a huge selection. Just be careful to read the fine print. Some of them are polarized. I ended up buying a couple low amp single pole breakers to use as switches. Being polarized isn't a problem since the power will flow one way only for this circuit. I didn't know they were polarized until a few seconds before installing them. I peeled back a sticker and found another sticker (or maybe it was the breaker itself) that indicated the breaker was polarized. I had to do a quick google search to figure out which way to wire it.