Results 1 to 8 of 8

Thread: Crate BT-100 Blows Fuse as soon as it's turned on

  1. #1
    Junior Member
    Join Date
    Apr 2017
    Posts
    4

    Crate BT-100 Blows Fuse as soon as it's turned on

    I have a Crate BT-100 Bass Amp that blows the fuse as soon as it's turned on. It seems to be shorted to ground, and component on the board shows an ohm reding to ground.

  2. #2
    Old Timer
    Join Date
    Jun 2007
    Posts
    4,925
    Welcome to the place.

    When an amp blows fuses at turn on, that usually means a shorted output transistor or a shorted power supply diode. It will take some work to figure out what your problem is.

    What sorts of experience do you have in repairing electronics stuff and what sorts of test equipment to you have?

  3. #3
    Junior Member
    Join Date
    Apr 2017
    Posts
    4

    Bill, I'm a Network Engineer

    Quote Originally Posted by 52 Bill View Post
    Welcome to the place.

    When an amp blows fuses at turn on, that usually means a shorted output transistor or a shorted power supply diode. It will take some work to figure out what your problem is.

    What sorts of experience do you have in repairing electronics stuff and what sorts of test equipment to you have?
    I've repaired plenty of computers, monitors a,d switches/routers. I have a multimeter. I also have a desoldering station and soldering iron. The only power supply repair I have done is for bad caps. I do have the schematic save on my laptop.

  4. #4
    Stray Cap DrGonz78's Avatar
    Join Date
    Oct 2011
    Location
    Scottsdale, AZ
    Posts
    1,675
    I think you should build a Light Bulb Limiter (aka Dim Bulb Tester). Whenever you have an amp that is blowing fuses the Light Bulb Limiter will help limit current if a short is present and will save your fuse. Also, once you fix the problem the first power up of the amp can be questionable still. With the limiter in place it can help prevent damage to the repaired amp if there might be anything shorted that you missed. So do a search for Light Bulb Limiter and build one. Stick to 60-100 watt incandescent light bulbs.

    When the going gets weird... The weird turn pro!

  5. #5
    Junior Member
    Join Date
    Apr 2017
    Posts
    4

    I will try this tomorrow.

    Quote Originally Posted by DrGonz78 View Post
    I think you should build a Light Bulb Limiter (aka Dim Bulb Tester). Whenever you have an amp that is blowing fuses the Light Bulb Limiter will help limit current if a short is present and will save your fuse. Also, once you fix the problem the first power up of the amp can be questionable still. With the limiter in place it can help prevent damage to the repaired amp if there might be anything shorted that you missed. So do a search for Light Bulb Limiter and build one. Stick to 60-100 watt incandescent light bulbs.

    I'll post the results

    Thanks!

  6. #6
    Old Timer
    Join Date
    Jun 2007
    Posts
    4,925
    It will be helpful if you post the schematic here, then we can all refer to the same part numbers, etc. when discussing what to check and test.

  7. #7
    Supporting Member
    Join Date
    Dec 2009
    Location
    UK
    Posts
    2,912
    +1 on building a bulb limiter.

    A couple of other points; Don't power the amp on with a speaker or other load connected. Also, to check if one or more of the output transistors are shorted, connect your bulb limiter and with your DMM probes connected to the speaker output briefly turn on the amp and measure if there's any DC on the output. If there's no DC you most likely have a PSU fault. The amp will 'hold' without blowing the fuse with a bulb limiter connected, but it's not a good idea to leave it running like this for more than a few seconds.

  8. #8
    Junior Member
    Join Date
    Apr 2017
    Posts
    4

    Crate BT-100 Schematics and parts list

    Quote Originally Posted by 52 Bill View Post
    It will be helpful if you post the schematic here, then we can all refer to the same part numbers, etc. when discussing what to check and test.
    crate_bt100_sch_and_parts.pdf

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Workingman's 15 blew a fuse when turned on. (help me troubleshoot?)
    By Stratapastor in forum Maintenance, Troubleshooting & Repair
    Replies: 90
    Last Post: 02-03-2017, 06:19 AM
  2. Tsl 602 pops fuse when turned off
    By madkatb in forum Maintenance, Troubleshooting & Repair
    Replies: 8
    Last Post: 10-11-2015, 03:36 PM
  3. Replies: 8
    Last Post: 03-23-2012, 04:39 AM
  4. B-52 AT100 very low volume/fuse blows when standby turned off
    By godwang in forum Maintenance, Troubleshooting & Repair
    Replies: 4
    Last Post: 12-15-2009, 01:34 AM
  5. Acoustic 370 blows internal fuse when turned on
    By KeyWestBassPlayer in forum Maintenance, Troubleshooting & Repair
    Replies: 35
    Last Post: 11-24-2009, 08:11 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •