Nord User Forum

Thank you for the quick reply Pablo. Can you recommend a link to where I can purchase the proper fuse? It appears there are lots of different kinds.

Thank you,

Jason

Hi Pablo, does this look correct? Thank you, Jason
http://www.grainger.com/product/6F024?g ... 27220335:s

I have not seen a fuse which looks like the one in that picture before

I get these inquiries once/twice a year and each time have to rerun websearch because the seller I found six months ago no longer has them

One would think that it would be possible to find a single consistent supplier, but I have never been able to find one in nearly six years

Last time around I ordered lots and have personal stock which I can sell inside US, but do not conduct business here in this forum. If you like to talk about that, please contact me at work as shown below.

Bless,

Pablo
pablo.mastodon@americanmusicandsound.com
800-994-4984 x3030

cutmyearoff wrote:Hi Pablo, does this look correct? Thank you, Jason
http://www.grainger.com/product/6F024?g ... 27220335:s

That's an indicating fuse, and though it is slow blow, it's also super expensive at $5 a piece. The simple one you need is more like 5 for one dollar. A search on Amazon for 300 mA Slow-Blow should give you many useful results.

Arjan P wrote:

cutmyearoff wrote:Hi Pablo, does this look correct? Thank you, Jason
http://www.grainger.com/product/6F024?g ... 27220335:s

That's an indicating fuse, and though it is slow blow, it's also super expensive at $5 a piece. The simple one you need is more like 5 for one dollar. A search on Amazon for 300 mA Slow-Blow should give you many useful results.

The Bussmann MDL-3/10-R is the same part that shipped from Nord in my Electro 3. I see nothing at all wrong with ordering this part (except the cost maybe). You could search for the manufacturer's part number to find the best price (or better yet available local to you).

As Arjan P suggested, the slow-blow ought to work just fine...

I agreed with Arjan P in my initial post (prior to this edit), but I did some further reading. "Slow-blow" or "time-delay" are terms that mean similar, but not exactly the same thing to different manufacturers. I compared another manufacturer's datasheet "Time-Current" curves to that of the Bussmann part. Unsurprisingly they differed: The manufacturer I looked at exhibited a "Time-current" curve showing it would blow slower than the Bussmann part. --This is potentially a very bad thing.

I initially thought "slow-blow" fuses blew faster than "time-delay" so would pose no risk of damage to your Nord. However,I was wrong in thinking that being true always:
The only safe course is to compare the datasheet of any replacement fuse to the Bussmann MDL-3/10-R datasheet. If it blows faster or the same as the MDL-3/10-R, it is okay to use. If it blows slower, your Nord could be damaged.

I can only recommend buying parts from a reputable manufacturer whose up-to-date datasheets are easily found on their website (not on a third-party website) so you can make this comparison. Unfortunately, we don't know how much over-current safety margin Nord's engineers built into their designs. So the best we can do is compare to the fuse they ship.

I think Nord ought to provide a list of approved replacement fuses since they make fuse replacement accessible to users.

Pterm, though you are right that not all slow-blow fuses have the same time/current characteristic, it is not true that so called 'time delay' fuses are defined differently from slow-blow. Slow-blow is simply a different term for the same thing (less 'PC' if you will ). But you are right, taking the datasheet from the originally delivered Nord fuse and findeing a replacement on that basis is a good idea. Or ofcourse contacting Pablo to get you the correct one!

Arjan P wrote:Pterm, though you are right that not all slow-blow fuses have the same time/current characteristic, it is not true that so called 'time delay' fuses are defined differently from slow-blow. Slow-blow is simply a different term for the same thing (less 'PC' if you will ).

I thought this too at first, but I need to disagree with you on this because the Bussmann catalogue includes what they call "Slow Blow" (MCRS series) and Time-Delay (MDL series). For a 1A fault current, the 300mA MCRS characteristic shows the part blows in 0.1seconds. At the same fault current, the 0.300mA MDL part blows close to 7seconds (a factor of nearly 70X).

OK, I hadn't researched Bussman that deeply. Learn something new every day.. Unfortunately brands I'm used to aren't always that clear in their distinction and use both terms mixed.

Anyway, with the question at hand, and your original Nord containing the Bussmann MDL-3/10-R, an equivalent of that should suffice. Bussmann calls it a time delay fuse that blows after 5-120 seconds with 200% load, or after a maximum of 60 minutes with 135%.