Motor Max Fuse Size Tables?

[majesus]

Just some info Req:

Does any have or know where I can get a table that shows the max fuse sizes (Time Delay) that can be used by code (CSA if possible) for a particular motor (@ a specific Voltage based on its FLA)

I could make one, for example at 600V (575V motors)

Motor FLA Max Time Delay Fuse
10HP 11A 15A

50HP 52A 80A

 

[davidbeach]

I don't know about the CEC, but the NEC lists motor sizes and code FLA. The Code also includes sizing for various types of overcurrent devices in terms of % of FLA. The final piece of the puzzle is the list of the standard sizes of overcurrent devices. A few minutes with the code book and excel and you will have your table.

 

[dpc]

I have a nifty little "slide rule" from Bussman that does just that, although this is based on NEC.

I'd contact Bussman and Shawmut, I'm sure they will be happy to help if it might sell a few fuses.

 

[majesus]

Hehe,

Thanks guys, slide rule is an awesome idea. I'll have to ask for one!

I started making an excel spread sheet. So far it is just for single motor branches: HP, FLA, TD Fuse and Cable size... man what a time saver then grabing the calculator and flipping through the tables.

 

[rob46]

Please see Cutler Hammer "Consulting Application Catalog", Table A25 of Power Distribution System Design section.

 

[majesus]

Ah ha! Yup, that is what I was looking for Rob46. This is excellent info for NEC requirements (althought I did make a table for the CEC.)

Just a note: It is Table A24, of the old Consulting Application Catalog (pg A-58, Jan 1999)

http://downloads.eatoncanada.ca/dow...m Design/Power Distribution System Design.pdf

And Table 1.5-2 of the recent catalog (pg 1.5-7 June 2006)

http://www.eatonelectrical.com/unsecure/cms1/TB08104003E.PDF

 

[waross]

This information used to be Table 26 in older versions of the CEC.
In the 1998 edition of the CEC it was moved to table D12.
(Appendix D Tabulated General Information)
In the 2006 edition of the CEC it is Table D16.
See also Table 29 in either edition of the CEC for percentages.
Please note: The NEC refers motor horsepower to a table which gives the motor current to be used based on motor horsepower rather than nameplate ratings.
The CEC uses nameplate current.
respectfully

 

[advidana]

Try SQ- D I think they have the best slide rule available. I have used it for many years. They have an updated slide rule every few years. your square D rep will get you one. This slide rule is based on both code and and testing of different size motors.

 

[majesus]

Hehe, thansks advidana. I called my local sq-d rep and requested it.