[work-log] Mini-cascade R-507/R-1150

[tiborrr]

Hi,

yeah, manometres will be bend so they will fit well below the frame, i just did not find any time to bend them . I still need one more wooden plate to cover the top. Frame is basically there to make transportation of the case easier. Now i can carry this cascade by myself, before not even two people could carry it comfortably because you couldn't get the grip properly.

Thanks again, teyber!

Best regards,
Niko

[runmc]

Very professional work Niko I am excited also to see the finish.

[[XC] gomeler]

Hope you have better luck tuning such a build than I had. Had a huge issue with the 1st stage not getting the HX cold enough and resulting in insane 2nd stage pressures. I ended up cheating and dropping in a 1/2 hp rotary compressor

[teyber]

wern't you using the nf5.5clx.2 though?

[[XC] gomeler]

I started with an NF9FX and NF5.5CLX and ended up with a 1/2hp rotary on the 1st stage and an FF12HBX on the 2nd stage.

[tiborrr]

Thanks everyone!

-100°C club on uninsulated cascade (massive heat loss due to almost 120°C deltaT):



1.stage (R-507):
HP: 13bar
LP: 1.4bar
static pressure: 10.5bar

2.stage (R-1150):
HP: 16.5bar
LP: 1bar
static pressure: 11bar

First stage is probably fairly overcharged (1.stage cap is now trimmed to ~ 1.7m 0.7mm), will tune more when unit gets insulated.



YouTube video:



P.S.: Piotres, sorry, i hadn't had time to check PM's, will read them later today. Sorry for delay, bro'!

[piotres]

Hi

-100 is nice but ...

Why You haven't wrapped captube over flex hose, only use some nylon strips to hold it ? that should help with some subcooling gain ...

16.5 bara without load on 2nd stage is quite high, I'm afraid with 200+W load put on evaporator this pressure will go to near 20 bara which will be too much for NL11F ...

but we'll see.

No problem with PM, I'm not in hurry too.

Regards

[tiborrr]

Hi,

I have wrapped captube around suction as much as i could, it's just my suction is very long (2m) and i'm using 0.8mm capilarity tube. I am guessing that this exposed evaporator & tubing already makes high load.

Evaporator:
Q = m * c * dT
Q = 0.5kg * 0.385 kJ/kgK * 120K = 23.1kJ (needs about 5min to pulldown)

P = 23.1kJ / 300s = ~ 77W average heat load

We have to add the heat loss from flex hose (2m), filter/drier on 2nd stage and crapload of tubing (also on first stage suction). I am guessing i am already putting more than 100W of load on cascade. We will see how the ethylene pressures are going to be once the cascade is insulated and only then re-tuned For my first cascade build i think i did a fairly decent job, don't you think so?

Best Regards,
Niko

[kayl]

nice work there tiborrr, love the music sets the scene when your hitting -100c

[piotres]

Hehe nice video now I saw it Yes fine captube is wrapped I see that on video . In case of such long suction line 0.9mm captube is good choose or even 1.0 mm . Only I don't like music on video

[tiborrr]

Haha, thanks kayl & Piotres! Tomorrow i'm off to local HVAC/R shop to get some neoprene insulation tubing in order to mount them on Wednesday when i return home!

Best regards until the next batch of photos!

[Clemmaster]

Hi,

I have wrapped captube around suction as much as i could, it's just my suction is very long (2m) and i'm using 0.8mm capilarity tube. I am guessing that this exposed evaporator & tubing already makes high load.

Evaporator:
Q = m * c * dT
Q = 0.5kg * 0.385 kJ/kgK * 120K = 23.1kJ (needs about 5min to pulldown)

P = 23.1kJ / 300s = ~ 77W average heat load

We have to add the heat loss from flex hose (2m), filter/drier on 2nd stage and crapload of tubing (also on first stage suction). I am guessing i am already putting more than 100W of load on cascade. We will see how the ethylene pressures are going to be once the cascade is insulated and only then re-tuned For my first cascade build i think i did a fairly decent job, don't you think so?

Best Regards,
Niko

The job is very nice, the choice of components "isn't really" (it could be worse of course) .
What's the suction temperature of the first stage? Still near -35°C unloaded? nl11f is a LBP R134a compressor, it's not supposed to run with R507c and even less at "high" suction temperature. You made a good choice with the decent condenser of first stage, we'll see once the system is loaded but you will run near the motor limits, maybe on both stages
Keep up the good work

[teyber]

congrats dude!

time for you to PM a mod for the -100c club

and you need a new avatar

[sdumper]

Ok I give up I dont see the pictures or the video am I simply missing it somehow?

[tiborrr]

Thanks for your input, Clemmaster! I hope that by tomorrow when I insulate everything about the discharge pressures & suction temperatures will be known.

@teyber: Thanks a bunch, dude! I will do as told

@sdumper: Check out post #31. If for some reasons pictures aren't displaying for you, i can upload them to imageshack.us too.
Here's a link to YT directly: http://www.youtube.com/watch?v=WcSpCnwgzFk

Thanks once again to everyone for their input, thoughts and critics!

Best Regards,
Niko

[sdumper]

Youtube worked fine!! Great job
Thanks man something weird is going on maybe its my browser:

[bartx]

Nice to see finished unit -100C looks serious

[tiborrr]

Thanks guys, this means a lot to me!

Today I brought home insulation tubing needed to properly insulate this cascade, but it will have to wait until tomorrow morning due to Christmas celebration.



Retention clip is made by Duniek, backplate was made by LittleDevil. Great work you two!

P.S.: @sdumper: I hope you see the images now.

Regards,
N.

[mytekcontrols]

Great results, and very cool demo video

And to think that is without any insulation.

Well let's hope that it satisfies this guy: http://www.youtube.com/watch?v=7dUZU...eature=related

(found it on same page as your youtube video)

[tiborrr]

@mytek: Haha, i seen that before Thanks for your kind words

Moonman & myself have insulated the cascade (still without it's maiden name):


Discharge pressures have dropped now significantly:

1.stage:
HP: 10bar
2.stage:
HP: 12.5-13bar

These chineese K-probes report about 10°C higher temperatures (around -93°C).

[Crazy666]

tiborrr
Beautiful unit, I’m envying you
Good work

[tiborrr]

Mini-cascade hold cca. 204W load at ~ 83°C, idle -92°C (measured with cheap chinese probe, that's about ~ -93°C, idle cca. -102°C), pressures are as followed:

1.stage:
HP: 14bar

2.stage:
HP: 17.8bar

Heating device - C2D E8600 CPU priming @ 5550MHz, 1.72V :


We couldn't have tested more than ~ 205W load due to instability of the CPU. We will soon higher heat load with Pentium 4 641 and also try to replace the probe with more accurate (brown as shown in previous post) one next time we disassemble evaporator hold-down.

Best regards,
tiborrr & Moonman

[piotres]

What probe You name as a "good" one (and where did You buy it) ??

Do You have dummy load ? If not it's worth building ...I'm very interested to see how dual NL11F will cope with 210-250W dummyload

Regards
Peter

[sdumper]

P.S.: @sdumper: I hope you see the images now.

Regards,
N.

Yep and it looks great!!

Very nice work

[tiborrr]

Hi Peter!
No, i don't have a load tester, i'm an overclocker not a builder so dummyload doesn't mean much to me The old probe is made by sharp out of thick K-line (chromel/alumel), it shows around -190°C submerged into liquid nitrogen, these cheap ones stop at around -173°C under LN2.

Will try ~ cca. 250W load with P4 641, but i think that's about the maximum for this system. It's funny, but i couldn't get more than 205W of heatload stable, processor just didn't want to cooperate Ofcourse, as i stated in the first post - this is dual-core benching cascade so 200-250W is over the head.

@sdumper: Thank you very much

Best regards,
Niko