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Help needed identifying onboard fuse

Jshiloh

Nov 15, 2018
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Nov 15, 2018
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Hi, I am looking for some help Identifying a fuse that blew on a circuit board that i am trying to repair. I have attached 2 images showing the fuse. on one side there is a square with either a 5 or an S in it (I am assuming that is the logo but unsure who the manufacturer is), and on the other side it says T25. I have been searching online for about an hour and cannot seem to come up with anything to tell me what this fuse amp rating is. Any help would be greatly appreciated. Also this is on a Siemens Microtech 3 controller. Thanks again for any help

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Tha fios agaibh

Aug 11, 2014
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Aug 11, 2014
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Often the amp and voltage ratings are marked on the metal ends. You may have to clean off the solder to find markings.

Any clues on the board itself that may suggest what it may be rated?
 

dave9

Mar 5, 2017
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Mar 5, 2017
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Determine where it is in the circuit then see if the following document is helpful. It seems the Siemens now goes under the name Daikin? It has diagrams for multiple models with fuse current and you'd pick a voltage rating above that shown for that part of the circuit.

https://www.daikinapplied.com/o365/...19-3_LR_MT-III_Controller_for_AHU_Manual.pdf/

Keep in mind that a blown fuse is often a sign it did what it was supposed to do, blew because some other fault is causing excessive current. If you only replace the fuse, it may just blow again, or risk further damage or even fire (but probably will just blow again).
 
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Jshiloh

Nov 15, 2018
3
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Nov 15, 2018
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thanks all. after 2 hours of looking, i did find some literature on the Microtech telling me it has a max pass through current of 4amps at 24VAC (dimensions 2.3mm x 8.mm) . I also found that the fuse brand is Schurter.

Dave9
the fuse was originally blown due to a short in another component in the unit i was working on. Also Daikin calls it the MicroTech III, but it is manufactured by Siemens. the Siemens part number is POL687.70/MCQ

hope this helps someone in the future having this same issue. again thank you for the responses.
 
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