What size thermal?

[Uglydog]

I need to up size the thermals on my WT 1100 DP.
She came without a motor. I mounted a 2 speed 3 phase (attached spec sheet).
I used the existing switch box on the DP.
It has Allen Bradley W41.
Which keep blowing, she cools and works well again.

My interpretation of the AB chart

http://www.ab.com/en/epub/catalogs/...1726/10551021/10551660/Product-Selection.html

suggests I need a W50. I don't understand what the differences between charts are.

Can anyone confirm?
Please.

Thank you,
Daryl
MN

 

[Dave Smith]

Daryl--did you look at the selection index to determine which table to use--I used to know all this information but it has been over 10yrs since i worked with heaters---I still have some in my supplies but I would have to locate them--you could try a couple sizes above the ones that are tripping untill you reach the size that don't trip---do you have a supply of heaters to try--maybe an electrician will answer your question exactly---Dave---*let me know if you want me to find my heater supply

 

[Uglydog]

Daryl--did you look at the selection index to determine which table to use--I used to know all this information but it has been over 10yrs since i worked with heaters---I still have some in my supplies but I would have to locate them--you could try a couple sizes above the ones that are tripping untill you reach the size that don't trip---do you have a supply of heaters to try--maybe an electrician will answer your question exactly---Dave---*let me know if you want me to find my heater supply

The type W has a protrusion as can be seen in the pics.
http://www.ab.com/en/epub/catalogs/12768/229240/229248/10521726/10551021/10551660/Introduction.html
Ebay shows them for around $10 each. I'll need two of which ever size is correct.

I'm hoping to visit you over Spring Break if you have thermals that meets the spec I'd rather get them from you.
Other than the N(?) that came off my Gisholt I don't have any laying around.

The charts don't make any sense to me.
But it looked like the W50 would work.

Daryl
MN

 

[Ulma Doctor]

I need to up size the thermals on my WT 1100 DP.
She came without a motor. I mounted a 2 speed 3 phase (attached spec sheet).
I used the existing switch box on the DP.
It has Allen Bradley W41.
Which keep blowing, she cools and works well again.

My interpretation of the AB chart

http://www.ab.com/en/epub/catalogs/...1726/10551021/10551660/Product-Selection.html

suggests I need a W50. I don't understand what the differences between charts are.

Can anyone confirm?
Please.

Thank you,
Daryl
MN

Hi, Daryl
A W50 @8.7 amps per leg with a size 0 or size 1 contactor

the difference between charts is the size and type of contactor

the smaller the contactor the less current it can handle
a single phase contactor will need to carry more load per leg than a three phase contactor for the same size motor

 

[Uglydog]

Hi, Daryl
A W50 @8.7 amps per leg with a size 0 or size 1 contactor

the difference between charts is the size and type of contactor

the smaller the contactor the less current it can handle
a single phase contactor will need to carry more load per leg than a three phase contactor for the same size motor

Thank you!
I made a lucky guess.
Any suggestions as to how I can best know if I have a size 0 or 1 contactor?
Are they labeled?

Daryl
MN

 

[Ulma Doctor]

most times contactors are labeled as to their size,
some have their size encoded into the model # or in rare cases in their serial #

 

[twstoerzinger]

Daryl, I must be missing something. What are the rated amps on the motor?
For a two-speed, I guess you have to go with the higher of the two ratings.
Terry S.

 

[Uglydog]

Daryl, I must be missing something. What are the rated amps on the motor?
For a two-speed, I guess you have to go with the higher of the two ratings.
Terry S.

My error.
I neglected to click the select all when I attempted to attach the motor spec!
Please note the attached.

Yes, it's alot more motor than a DP needs. But, the price was scrap price at a moving sale where he was trying to clean out the garage prior to moving south. His wife was packing the RV refrigerator and the home For Sale sign was marked sold.

Daryl
MN

 

[jim18655]

Different charts for different applications. Enclosure type also dictates element size. Ambient temperature for the motor and controller location can affect heater size. Open style refers to a large cabinet mounted starter where it may cool better. Some heater elements are "ambient compensated" to account for controller not installed by the motor. Use the index tab at the top of the charts to select the proper chart. I think you got the right size based on the limited information provided. Heaters also change size based on the size of the starter they are installed in.
Two overload blocks connected to one starter and selected based on speed would provide the best protection but that is not possible with the starter you have.

 

[rdhem2]

Mr. jim18655 has all the right answers.

You have two choices. Only wire one speed of the motor with the proper size heaters installed or get a two speed magnetic starter and install all six heaters of the correct size. Why six? Three for each speed same as your single speed contactor needs three for one speed. Why? Code requirement for proper safe operation. If your starter only has two overloads it is out of date and non code compliant. One heater is required for each current carrying leg of a 3 phase motor circuit. Sorry, have to keep up with the times. Anything else is bad info.