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Information about Noise-killers & Fan-regulators


This document contains information related to the testing of different psu-fan regulators. First of all the GETO-TECH noise-killer, and then the fan regulator of PSU(2).

[ index ]

(If you don't understand what you are reading here, it's just states that the noise killer bough from a local-online store in norway was a great dissapointment.)

Vifteregulator kjøpt fra komplett data ( www.komplett.no )  for kr. 150,- Ingen informasjon følgte med, søk på nettet på produsentens navn (GETO TECH) førte til følgende informasjon.F1000018-crop-noisekiller-.jpg (2957 bytes)

Geto Tech, Kr.sund Verkstedveien 4, 6500 Kristiansund Tlf: 71582802

http://www.nettkatalogen.no/aa/getotech.htm - Web firma informasjon

Kunne ikke finne noen informasjon annet enn dette fra produsenten på nettet. Konklusjon : Ikke så hotte greier.Ingen hjemmeside. Ingen informasjon pr. 1999.

Oppdatering 2001 : Firmaet har nå en hjemme-side : www.geto.no

Noise-killeren var en ned-tur. Den regulerer ikke så bra som jeg hadde håpet. Men men, kanskje bedre en ingenting.

Antar at noisekillere stort sett er bygd på samme prinsippet, så her er en site med noe mer utfyllende informasjon om tema : [ HOPP ]


Update : Videre undersøkelser av  Noisekiller'n.

Videre undersøkelser av greia, viste at den regulerer med volt. Ikkenoe puls greier. For å kunne målle utspenningen, trenger utgangen å ha last.

Det som er bra med den uansett, er at den har en viteboos som kan brukes til noe. Svakheten er at den skruer aldrig helt av. Den går ned til ca. 3 volt, som vel er minimums-spenningen for å holde en 12 volts vifte gående. Å sette inn en zener-diode her vill mulighens kunne stoppe den helt.. Det andre problemet er med selve temperatur reguleringen. Kan ikke se at den regulerer spenningen opp som følge av endringer i temperaturen. Holder på og undersøke dette. Det virker forsåvidt som om termistoren faktisk virker. (Noe jeg fant ut etter å ha klippet greia i stykker). Den oppererer med verdier i områded under 1 kilo Ohm. Trodde en vanlig verdi var ca. 10 K Ohm. Men men . Dersom det går an å modefisere det slik at den virker i  et temperatur intervall på mellom 30 og 50 grader ville det vært flott. Kommer tiilbake til dette senere. [ Se lenger ned ]

Problemet er uansett generelt. Har ikke kommet over en eneste en som har virket. Kanskje jeg har hatt uflaks. Men viftereguleringen har ikke virket i noen av de PSU'ene som jeg har hatt. Med unntak av den siste (PSU (3)i) .

Det ser ut som om jeg må lage min egen dersom jeg er intressert i å få en som fungere.  Det er jo selvsagt begrenset hva du kan få for en hundre-lapp.


Update : Case study of noise-killer(1)

I decided to see if I could understand why the noise-killer doesn't work as well as I   had hoped for. Set up a test-environment to measure, monitor and manipulate the unit. The results of this work are contained in fragments below. I might test other regulaters as  well, hoping that they may be better than this one.

Essense :

The main problem that the regulator has is that it's dynamic range of operation is to wide (in terms of temperature) and too small in magnitude.
The magnitude of dynamic regulation is 3 Volts in the range of [19 .. 67] C,  with fan output voltages [6 .. 10.4].

In the range [30 .. 40] C, which is of particular intresst from a cabinett ventialion point of view, the thermistor ragne is [560 .. 383] Ohm's ; A variation of 180 Ohms. Assuming linearity between termal resistance and fan-voltage this gives a fan output control range of 0.8 Volts !!!!!

In other words, changes in fan speed are not likely to be of such a magnitude that you'll notice. Static. Totally undynamic.

Alternative uses :

After concluding that it has been  floppy created, and dropping all "I might get it to work anyway"-plans. Alternative uses where considered. The main benefit that it has is the built-in fan-"booster". This gives a fan the extra power-boost it needs to get going when starting up, and is the main advantage over a pure resistor regulation alternative. (messed with this stuff in part 1).

  1. Adjustable regulator : With +12 voltage in,  and using a 1 k Ohm pot meter instead of the termistor, voltages can be regulated continuously between [6.0 .. 10.4] volts.   Suitable for tuning static cabinet fans maybe ?
  2. Static regulator : With +12 voltage in, it gives 6.0 volts out. In addition it boosts fan voltage to 10.4 volts at power on.(medium)
  3. Static regulator : With +7 voltage in, it gives 3.77 volts out. In addition it boosts fan voltage to 5.? volts at power on. (slow)
  4. Static regulator : With +5 voltage in, it gives 3.45 volts out. In addition it boosts fan voltage to 4.2 volts at power on. ( very slow)

Note ! For the static regulator in point (2) above  the thermistor has been disabled (or cut away) leving this input with an opencircuit and infinite resistance.   Which gives minimal fan speed.

In the case of 3 and 4, it doesnæt matter what you do. Resistance on termistor input have no effect what-so-ever.

In case you don't know how to get +7 volts. Use +5 V (typically red wire) as virtual-ground, and +12 volts as positive. The difference between them is 7 volts- I don't know wheter this might disturb some balance in the PSU (thinking about HF noise) but I haven't verifyied or checked this out yet.

Other stuff :

Some boring measurements that I don't bother to enter. But here is some facts ...

 

Thermistor input (resistance) : Fan output (volts) :
open circuit / infinite 6.00 volts
short circuit / zero 10.40 volts
270 Ohm 6.7 volts
1000 Ohm 6.0 volts

Fan output voltage range : [6.00 .. 10.40] Volts.

Termal sensor-input range : [1000 .. 0] Ohms.

Termistor range (verified) vs.resistance : [17.6 ..  67.6] C maps to [925 .. 157] Ohm's.

Termistor type : 1 k Ohm. ( max. at room temperature of 17 C )

 

[ index ]

Update : Exploration of noise-killer in PSU(2) Seventeam

 

Noise killer runs on 6.0 V static up until around 45/50 degrees, where boosting starts. It is not possible to run this module on +5V or +7V it won't start. There is no fan-booster in the circuitry. Reduction in fan-speed may be done by inserting a resistor in series with the fan. At what value I don't know, yet but seem to remember that a 270 Ohms did the trick (from part 1).

Since there is no fan-booser the voltage need to be set so high that the fan starts up. If it works on 4 volts, that would be a 2/3 reduction in peak range as well ... meaning max. speed would be around 7.2 Volts. Need testing.

An interesting observation is that the dynamic control range is in [50 to 70] C, which suits me very well given the outcome of the silencing project of this PSU. [see else where]. It may also serve as an indication that the PSU itself is specified for operation in the range up to 70 C, and not 50 C as assumed. There will be no boost in fan-speed until this temperature is reached.

 

Thermistor input (resistance) : Fan output (volts) :
open circuit / infinite 6.00 volts
short circuit / zero 10.80 volts
infinite to 4 k Ohm 6.0 volts
2 k Ohm 10.3 volts
150 Ohm 10.8 volts

Fan output voltage range : [6.00 .. 10.80] Volts.

Thermal sensor-input range : [ 4 k .. 0] Ohms.

Thermistor range (verified) vs.resistance : [16.5 ..  66.8] C maps to [14 k .. 1.92 k] Ohm's.

Thermistor type : 14 k Ohm ( @ 16.5 C ambient temperature )

Temperature dynamic range : [45 ... 70] C maps to [6.0 ... 10.8] Volts.


Update : Exploration of "noise-killer" in PSU(1) AOpen (OEM)

It is hardly worth spending time on. This piece of glued & bubbelgumm electronics regulates down to 10.4 V permanently. It is very likely that mine is/was defective so better working versions are probably in existance.


Another piece of information :

The information below where extracted from this link - http://noisekiller.2000c.net/

NOTE ! This information is for a totally different, produvt and is presented as a refrence point. It specs. tooks better than the one I've examined. Not detailed enough to tell wheter it's a good one though. Temperature control-range is a little bit too high, and to narrow. Doesn't say anything about minimum fan-output voltage. etc.

Technical data of Noise Killer

Supply voltage: 12Vdc +/- 20% (available in any PC)

Max. load current: 500 mA (more than enough!)

Standby power: approx. 25 % (saves energy!)

Maximum fan speed: > 97 % of nominal. (for maximum cooling)

Noise reduction: 15 - 20 dB !! (sounds like 75-90% less!).

Ambient temp: 0°C - 50°C. (better than hard disk specs)

Temp. control range: 36°C - 38°C (+/- 2°C). (extra stable when hot!)

Size of module: 26 x 40 x 12 mm. (easy to fit)

Short circuit protection; virtually fool proof (not necessary for you)

Start booster for reliable operation with all types of fans. (safety first)


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