This week my order of 10 clixons (50c N.O.) arrived.....
And today i had time to add this to my latest PSU.....
So again i got rid of 13 screws....
And i looked at an empty spot where a clixon should be......
The holes you see there are only in the metal sheet they use for a heat sink... they are not drilled through.... which took me about a minute to fix.... 2 nice holes all the way through.....
I installed the clixon.....
You can see the slightly smaller black bolts i used to install the clixon. You would say this is as it came from the factory if you would not know better....
When wiring up everything, I noticed it that it would be better to rotate the fan 90 degrees, so the wire would exit the fan close to the clixon. (2nd picture)
The fan they use i this model is not (how surprising) an expensive one.... I might replace in time with one which is better (at least one with a ball bearing)
I am not sure yet as it might also be handy to have a "noise" warning if it becomes too hot.
After that it was just a bit of soldering and the job was done.....
I put back the cover, screwed in 13 screws.... and reinstalled it on the shelf....
Again, I now have no fan noise if everything is in idle mode.... nice and quiet....
So from a silent shack, I wish you 73's!
Alex
PA1SBM
waar heb je de clixon besteld?
ReplyDeleteHier:
Deletehttp://www.ebay.com/itm/10pcs-KSD301-Temperature-Controlled-Switch-Thermostat-50-C-N-O-Normal-Open-/301193012567?hash=item462080a557
Hello Alex,
ReplyDeleteI also modified my PSU (same brand) with a 50°C Klixon. But I put a 200R /5W resistor in series with the fan. When the kixon switch on, the resistor is bypassed giving the full voltage to the FAN. If you want a picture I can send that to you. The resistor is soldered on the kliwon tabs.
Best 73s,
Philippe - F4GRT (at)sfr dot fr
Hi,
ReplyDeleteIf you _measure_ the temperature inside the case without its cover, you will find that some, not even active components will reach 55-60 degrees Celsius while the main heat sink is only at about 35 C - in response to a minimal, 2-3 amps continuous load...
So, I did not investigate it more, but given the clixon might have been the first option that considered not safe/adequate enough by the manufacturer for this PSU, I decided that this equipment definitely needs the always-on forced ventilation.
Moreover, if the fan is not turned on until 50 C (on the heatsink), it will be very silent for a while - then relatively loud for a while... Some prefer the continuous regulation, this PSU has it built-in. I have changed its original fan to a Noctua, and it is fairly noiseless for the usual load of the turned on equipments I have on my desk, but not enough noiseless, so I still need to build a linear one...
73 ..... Tibor
Hi Tibor,
DeleteThe fan in my unit is fairly silent as it is, and it only powers my dualband tranceivers, so no high load anyway.
I did this mod in all 3 of my other 30amps PSU's and it works like a charm... yes at the point it gets hot the fan goes on full, and it becomes somewhat more noisy (not much as i have papst low noise fans installed) and as the clixon needs the temp quite a bit lower to turn off, it cools it back down a lot. I used one of my PSU's for a IC7600 when in a 24hr contest. It turned on once, even though we were using full power.
in both types of PSU's the clixon is very close to the power transistors. so it will kick in on time.
As for the noise, in my own shack i never put much continuous load on my PSU so its always quiet. i rather have it turn on on a rare occasion then being on all the time on a low level. I try to have my shack audio noise free... i only want to hear my radio, and i manage to do so...
Thanks for reading my blog!