Topic: Official Avalon Technical Support Thread - page 14. (Read 48888 times)

Is it still recommended to remove the f1 fuse on batch 2 avalons. 

My batch 2 Avalon sometimes stops mining until the watchdog restarts cgminer.  Cgminer output looks like:

-snip-

I'm running the 0519 firmware.  I have removed the F1 fuse.

Thanks el_rlee! So P2 is unused, doesn't even have a header soldered to it.

I see you still have your F1 fuse on, the one that powers the USB-A connector. You should remove that. Get a cutter, and cut it in the middle.

Thanks for your reply.
Temperature is measured on two of the heat sinks. Cgminer shows 3 temperatures, I guess the third one is on the control unit itself. Interesting is the numbering of the fans with number one being in the middle IIRC...

I am not near my miners, but P2 is either the LED's on the front of the housing, or if they are connected somewhere else, empty.

Hello Avalon mining system users, I need a little help. On the Control Unit card, Version 1.5, there is a P2 header with 6 pins, near the JTAG1 and P3 headers. I know that the P3 header is for the thermal transistor that measures the temperature of one of the heat sinks. However, I don't know what the P2 header is for. Is there anything plugged onto this P2 header? Or are there jumpers? A picture of your Control Unit with the P2 header clearly showing would be a big help.

What type are the thermocouples used on batch #2 heat sinks? Do they have any function besides regulating the fan speed?
I want to water-cool my Avalon - should I put in a thermocouple or can I use a fixed resistor for instance?

NMB-MAT 7
Model 4715KL-04W-B56
Minebea-Matsushita Motor Corporation

Does anyone know the precise model number of the fans the Avalon units have in them stock or a possibly good replacement for them?

It all depends on the power supply. If the power supply has APFC (Active Power Factor Correction) it is highly recommended to use a UPS that outputs pure sine wave AC.

I believe that PFC power supplies should use true sine wave UPSs. The reason for this is that PFC power supplies require a much faster changeover time when the battery kicks in, and that due to the design of stepped sine wave UPSs, they were not always fast enough to satisfy the power supply. This could lead to the PSU shutting down when the battery tried to kick in. A stepped sine wave UPS wouldn't "damage" the PSU, but that it simply might not work, and that if it DID work, it might not "always" work. It all depends on the specific power supply. The UPS shutting down has happened to me when using a non sine wave UPS with a APFC power supply.

Most PSUs that you'd want to buy these days will have APFC.

The problem that I see here (and this has been discussed in another thread I believe) is that it takes a LOT of juice to keep an Avalon running so you're going to need a beefy UPS and even so most reasonably priced UPSs (1440VA) that you can attach to a 15 amp circuit are only going to be capable of keeping it alive for maybe a few minutes at full load (even less if you run it clocked at 300).

IMHO it's worth while to have a least one on a UPS so that if there is a brief blackout at least one unit is mining and you're not losing _as much_ money (in lost revenue).

Now as for what UPS to choose. Personally I recommend the APC SmartUPS series. I've been using them for a long time and they are very reliable units. The SmartUPS series output pure sine wave by the way.