Author Topic: Advice on inverter board  (Read 2502 times)

0 Members and 1 Guest are viewing this topic.

wpowokal

  • Hero Member
  • *****
  • Posts: 1271
  • Country: au
  • Far North Queensland (FNQ) Australia
Advice on inverter board
« on: June 22, 2011, 08:04:47 PM »
I have a inverter control board I am working on.


My confusion surrounds the resistors, the two on the left where you can just see a red band are Brown Black Black Silver Brown Red now I read that to be 1 ohm

The two horizontal ones are  Brown Brown Black Silver Brown which I read as 1.1 ohm

Now I have removed the crispied components and powered the boards (2) up and there is a signal at each of the horizontal resistors that gate the MOSFET's so I take this as an indication that the switching circuit is working and the original fault was dust and moisture across a MOSFET that cascaded from there.

Question...... have I got the values right (I actually used an on line calculator) because 1.1 ohm seems it may be a bit hard to sourse.

It may help to add that the MOSFET's are IRF3205 and since I will be replacing all on one side  (my term) eight off, I am concerned as to whether a small discrepancy in the resistor values will matter I would hate to have one half of the AC wave different from the other.  

Allan of the jungle
« Last Edit: June 22, 2011, 08:16:08 PM by wpowokal »
A gentleman is man who can disagree without being disagreeable.

rossw

  • Hero Member
  • *****
  • Posts: 834
  • Country: au
Re: Advice on inverter board
« Reply #1 on: June 22, 2011, 09:22:42 PM »

Question...... have I got the values right (I actually used an on line calculator) because 1.1 ohm seems it may be a bit hard to sourse.

We were chatting about your post in irc - here's the relevant bit:

11:10:39-23/06/11| <RossW> !resistor brown brown black silver brown
11:10:40-23/06/11| <RossBot> 5 bands, 1.100 Ohms 1.00%

11:10:42-23/06/11| <RossW> !resistor Brown Black Black Silver Brown
11:10:42-23/06/11| <RossBot> 5 bands, 1.000 Ohms 1.00%
 
11:11:11-23/06/11| <dang> he reads six bands on the verticals..  red as final band?
11:12:02-23/06/11| <dang> fusible
11:13:53-23/06/11| <dang> farnell has 1.1Ω 0.5w SMDs : p