temperature activated switch/outlet

[badkuk]

hi peeps,

Is there such a product?

ganito kasi: we have a small server room that needs cooling. We have an AHU in our unit, but we were thinking that it's way inefficient to leave the AHU running -- esp. on weekends -- just to cool off our server room(mga 17sqm lang).

So the idea is to use a portable AC, and either use its timer to turn it on/off, or use a temperature activated switch that will supply power to the portable AC once the room temp hits, say 30 degrees C.

We're more or less set on using the timer thing, pero we're just thinking that it may be more efficient to use temperature as basis. There will be time kasi that some of us may do OT work, hence the AHU would be turned on. Kung time based kasi there's a chance that both would be running at the same time.

comments? suggestions? tia

[testament11]

maybe a switch with a thermocouple will do. parang sa climate controller ng sasakyan, which na set to auto, yun thermocouple ang magtritrigger sa aircon na ganito lang ang operation niya. pag mainit, full blast. then pag normal room temperature na, nasa normal running condition ang aircon

[wowiesy]

Sa pagkakaintindi ko, the objective is to maintain the temp of the server room at the least cost possible.

If you are willing to experiment pa (which may or may not be costly but definitely time consuming also), there are a few information / data that we will need in order to be able to determine the most cost efficient way of doing this:
1. temperature range of the room - during weekdays na may work talaga w/ ahu on (min / max), during weekends na walang work (ahu off), during weekends na may mangilan ngilan na nag wo work

2. existing AHU capability - if its a basic aircon (na window type or split type) or if it is an industrial type AHU

3. possible result of using an exhaust fan and a high velocity blower on the temperature range of the server room during weekends of no work / minimal work...

If I will assume na ang AHU ay ordinary airconditioning (split type o window type)... i'll first get temperature readings to get the actual temperature range na no ahu, no work... if the room is really isolated from ambient temperature then mas simple ang data gathering.. but kung ordinary room sya and hindi insulated from other rooms, we have to take into account the relationship of ambient temperature versus the server room temp...

Anyway, as far as control components, you'll definitely need a thermocouple, temperature controller analog (cheaper) or pid (a little more expensive).. pinaka mura dito i think is kung gagamit na lang ng blower / fan sa room, then alalayan ng exhaust fan... the blower / fan will blow directly to the server equipment to remove the hot air in the components... then alalayan ng exhaust to dump the hot air outside the room...

sa ganitong setup, it can keep your server room temp stable but ang possible problem is the blower and the exhaust would have a difficult time bringing down the temp kapag mataas din ang ambient temperature sa labas.. in this case, kung talagang critical, baka kailangan na automatically on yung AHU for a 1 - 2 hours na naka preset na yung temp.. just to bring down the temp faster... then after the ahu is turned off... bayaan mo uli yung fan / exhaust combination to do its work.. kapag tumaas uli beyond the control of the fan / exhaust, papasok uli yung AHU... dito papasok kung anong klaseng AHU yung gamit.. if its the window type / split type aircon.. susceptible sya sa sira kung madalas ang patay sindi (bukod sa malakas sa kuryente pag frequent on / off) so you may have to set the temp on a wider range... kung industrial AHU naman na kaya yung more frequent on and off.. I guess uubra yung plano above..

sa server room namin, we have 2 servers (naka dual cpu, with 4 raid disks), 2 servers na clone machine lang, data cabinet (with the backbone switches)... minsan pag hindi nabubuksan yung aircon sa room, the room temp goes up as high as 35C... yung mismong casing ng servers umiiinit din... tinatapatan ko lang ng fan (yung 3d na parang industrial air circulator).. yng mismong mga servers.. iniiwan ko bukas pinto ng room para lumabas yung hot air... then napapa baba na nya yung temp ng room...

if you need further help on the details.. just drop me a note.. baka makatulong pa ako...

[CVT]

Wala bang thermostat ang iyong portable AC unit? Should be standard, right?

8404:duel:

[badkuk]

Wala bang thermostat ang iyong portable AC unit? Should be standard, right?

8404:duel:

ung setup sana is that the portable ac and the unit's AHU won't operate at the same time; i.e. if the ahu is on, the portable ac should be off. i seriously doubt if the building admin would allow us to butingting with the electricals of the AHU, i.e. manipulating the electricals such that only one or the other is on, so the only other way i could think of is to use the room temperature as a trigger for the portable ac to power on.

sir wowiesy, digest ko muna ung post niyo ha B) ganun nga ung problem namin, pagpasok tuwing umaga sobrang init ng server room...i'm pretty sure some equipment has already begun to break down since i've smelt burnt stuff more than once already. we'd like to leave the room locked for security, but because of this we leave it open, with a few industrial fans blowing directly into the servers. even the switches were getting hot!

minsan nga i got to thinking that this all may be too much hassle, e me "solution" na naman ngayon....then again finding a fried server when you come in for work is bound to ruin your day

[wowiesy]

hmm..

building AHU system... medyo mahirap nga kumonek dyan.. bali ang lamig / hangin lang na pumapasok is due to the ducting / vent na naka abang sa building / office? In some offices (at least sa office ng wife ko where she works), naka ducting nga sa ceiling.. but the AHU is still per individual .. meaning sa office nila, may sariling AHU na naka kabit sa mga ducting na yun.. they have to manually turn on or off as needed... so they pay for their own electric bill for that.. kasama na sa metro nila..

in your case.. kung building admin ang may control ng on / off ng AHU (centralized malamang), I suppose you don't have much choice but to install an aircon for your room separate from that provided by the building.. kung papayagan ng building admin. a portable AC unit... depende din sa laki ng room eh.. 17sqm... anong sukat ng elevation (floor to ceiling)? that's still a lot bigger than the internal of a car... so halos room AC unit na ang kakailanganin mo dyan...

another option is to use the evaporative coolers / fans type of fan..

another possible issue.. sa mga medyo bagong appliances right now like aircon (window and split type), evaporative coolers.. most of these ay may remote control na.. so kahit there is power sa mains going into the unit.. it is still the remote that controls the on and off.... if it comes to a point na gagamit ka na ng ganitong klaseng appliance.. hindi sya ganun kadali i turn on ... may karagdagang complexity (digital electronics interface ) to simulate the "on" command of the remote... unlike those older units na pupuwede mong iwanan yung unit na naka on, tapos saksakan lang ang mag determine kung may power o wala (naka hugot ba o nakasaksak)... but if you leave the appliance on tapos hugutin mo saksakan at ibalik uli at naka on pa rin sya.. I guess okay na.. but most of the ones I've encountered.. nawawala talaga power and you have to use the remote to turn it on again..

I'm mentioning this because I'm coming from the idea that it would be a relay or a contactor that would trigger the ON / OFF of the aircon / fans / exhaust.... basically industrial electrical components para mas sturdy at readily available...

there's a forum on the net: www.electronicslab.ph... you may be able to get more ideas there...

[wowiesy]

dagdag ko pala..

I'm not sure if you've found a portable AC unit.. pero assumption ko is aircon unit talaga.. and if you use a temperature control to turn it on and off... you have to be careful of the temperature controller you select for the purpose..

most temperature controllers just try to maintain a set temperature.. in your example say 30C... ang range nya is usually maximum 5C +/-.. so you can go between 25 to 35... the reason why i asked about the temperature range right now.. is kung masyadong mabilis magbago ang temperature (either masyado malakas ang aircon or masyado mainit yung servers).. baka masyadong mabilis yung frequency na pag patay sindi ng aircon.. baka dun madali masira... except if you use an ordinary fan / exhaust.. di gaano cricital yung patay sindi...


same as in a car... (but don't try this)... try mo i on / off ng maraming beses at mabilisan yung aircon... iiksi din buhay ng aircon system....

[woohoo]

Why don't you just set the room aircon to a max of 30 or 28 or whatever is optimal? That way, hindi masyadong mabibigatan yung aircon. May sensor naman yan.

[badkuk]

the plot thickens...

Pinayagan na kami, kaso ang bilin sa amin, wag daw ibuga ung exhaust ng portable AC into the AHU room. So either we bore a hole on the server room wall and vent the exhaust there(into the rest of the unit) or dun na mismo sa server room ibuga ung exhaust(not that efficient but it will work, right?)


*sir wowiesy:

the ceiling's about 7 meters.

hmm, di ko naisip ung behavior nga ng appliances to stay off when turned off.
i'd really rather not have to DIY the solution, not to mention void any warranties.



Me sources naman ng portable AC, problem is they don't keep it in stock.

Evaporative ACs are not an option: the humidity will kill our servers B) nasubukan ko na yan, we ate at this resto that was having ac problems, so gumamit sila ng evaporative ac. The air and the tables felt really damp, and lumala ung trangkaso ko. Kung di man ung servers namin ang masisira, kami naman ung makukuryente B)


Bale ung temperature would be a trigger lang to turn on the portable AC; once it's turned on, it stays on until the first staff that comes into the office turns it off and turns on the AHU.

[wildthing]

merun similar product being use in modern poultry houses... it is a thermostat switch.

pagnareach niya yung temperature na mataas (which can be adjusted to need) say 27 deg C, it would turn the fans on. Then it will turn off naman pag nareach niya yung desired working temp.

the sensors (puedeng multiple sensors) are located where it is necessary.

unfortunately, I forgot where to buy it locally.