Killed my Hub

[Ted]

Hi all,

Built the 6 channel master hub, temp/solar and moisture sensors and they were all working fine.

Today I was rewiring the moisture sensor and mistakenly put the 12 volt line into the ground connector of the moisture sensor .

Looks like I have killed the hub, damn.

When I connect the hub to the PC OneWireViewer finds the adapter but will not show any 1-wire devices or channels available.

What I would like to find out is which part or parts need replacing, any ideas?

Cheers - Ted

 

[ericvic]

Ted,

Does the green light come on? If it does then I would think you have taken out one or more of the DS2409 coupler chips. Those chips can be a bear to replace unless you have a good desoldering station which not too many people have (including us). If the light doesn't come on then it may just be the voltage regulator. The other thing to look for is burnt traces.

If you can post a picture of the Hub board I can try and help troubleshoot the problem.

Eric

 

[Ted]

Hi Eric,

The green light comes on and I don't see any burnt traces....

Now I've had a bit of progress, you mentioned the couplers so I had a look at them using a meter and there seemed to be an anomaly with channel 1. Reckoning there was an internal short I pulled that coupler (no kidding on trying to get them off the board!) and the remaining channels came up in the viewer, great!!!

Next I tested the temp/solar sensor and that works, then the moisture sensor and that seems to be dead.

Checked the 12v and GND lines and they were shorting so I pulled the regulator and bypassed it with a wire. Connected the DQ and GND lines only and the moisture board was available in the viewer... good.

So all things considered it could have been worse. I can source a regulator locally and I'll replace the coupler next time I order some 1-wire stuff.

Thanks for pointing me right direction.

Finally a quick question; the DS2760 on the moisture board seems to have a temperature sensor built in but it always reads zero in the viewer, is this usable for temps?

Thanks.

 

[ericvic]

Ted,

Glad to hear that you seemed to have tracked down your problems. If you are getting 0 degrees while you have the regulator off the board then that is what is causing the problem. I don't think the DS2760 will do a temp conversion without external power.

Eric