"fake" rpm sense

signal64 · Post by **signal64** » Sun Dec 17, 2006 5:01 pm

I don't think there is a magic answer to this one but thought I'd ask anyway.

I have a non-PC device that has a fairly noisy Nidec TA300DC 80mm fan.
12v 3pin lead, 35cfm @ 31.7 dBA (4.5 Bels) and looking at the specs runs about 2600 to 2800 RPM. The header on the fan isn't your standard PC type either (but can take care of that).

The problem is if I replace the fan with one that still provides enough air flow but doesn't run at the same RPM the device will consider it a failed fan. In that condition the device won't start.

Like I said, isn't a PC where I can bypass the sense/alarm in setup/bios.
It doesn't have a PC OS (not even an x86 based) and isn't modifiable.

I take it there's no way to fake this out externaly and I need to get a fan that runs at that RPM that is hopefully quieter?

Thanks

BTW - Tried a Panaflow @ 2450 rpm which didn't work.

Chris Chan · Post by **Chris Chan** » Sun Dec 17, 2006 5:31 pm

What exactly is the device?

Post by **Rusty075** » Sun Dec 17, 2006 6:25 pm

There's some info here: How to make RPM Signal for 2-Wires Fan, but its not exactly a plug-and-play type solution. There's a link to a good schematic here: Adding RPM Sensor to your Fan, but you'll have to be comfortable with a soldering iron.