Pauls HP UHU drive project

[BobVanDyke]

I have been trying to trouble shoot my HP-UHU board and found that R46 was shorted. When I looked at UHU MODIFIED_Dated1.4.08_R1.0b the schematic page 5 did not match the board page 6. Page 6 shows a trace from U12 pin 3 directly connected to U13 pin 6. This appears to make R46 redundant.

I have checked to see if this was referenced on any of the threads but was unsuccessful. Was this a known fault that I failed to read about?

Bob

[jcdammeyer]

Originally Posted by BobVanDyke When I looked at UHU MODIFIED_Dated1.4.08_R1.0b the schematic page 5 did not match the board page 6. Page 6 shows a trace from U12 pin 3 directly connected to U13 pin 6. This appears to make R46 redundant.Bob

Hi Bob,

Good point. I see the same connection on the layout drawing and on my board. What it appears to do is pull Pin 3 of U12 low as if an ESTOP happened.

I too must be missing something because no one has complained as yet. But then I haven't powered mine up yet. I'm only about 3 years behind.

John

[BobVanDyke]

I don't believe this is a problem. I wouldn't have even noticed it except R46 appeared shorted and I thought I made a soldering error. The board obviously works the way it is. I notified Tenmetalman, the owner of this thread, by E-mail and got a Help Ticket response from CNCzone. I just wanted to document this in case others thought they had a problem.

The kit itself was easy to assemble and looks great. I'm not electrical so I'm having a tech look at mine. The problem I'm having is the motor turns as if shorted to the high voltage power. Nothing to do with the Emergency Stop.

I was surprised that U12 and U13 have the legs numbered 1,3,4 & 6. That's the first time I've seen that.

Bob

[jcdammeyer]

Originally Posted by BobVanDyke [B] I was surprised that U12 and U13 have the legs numbered 1,3,4 & 6. That's the first time I've seen that. Bob

The package is a standard size and uses a standard footprint. Normally such a package has 6 pins. Hence the numbering.

John