Curing Oven questions

Discussions for scratch builders. For the enthusiast that builds from the ground up. Tell us what you've built and what projects you working on in the space race.

Moderator: Moderators

User avatar
SpaceManMat
Astronaut
Astronaut
Posts: 1643
Joined: Mon Dec 15, 2008 9:56 pm
Location: Brisbane

Re: Curing Oven questions

Postby SpaceManMat » Tue Mar 21, 2017 2:14 pm

SinfulDarkLord wrote:Of course on the drawing it says to hook it up to a 120V AC source, but the guy on youtube wired his to the terminals on the thermostat.


This would be either because the thermostat unit had a higher power rating or he was only using a small load (or enven possibly overloading the thermostat). Anyway the idea behind using a relay is to esentually upgrade your power handeling capacity. So the relay takes in the lower current that the thermostat provides and then provides a high current output to your heater.

Your diagram has both sides of the high current heater circuit going to pin 9. One of the wires needs to go to pin 10.
QRS: 124
AMRS: 32 L2 RSO
Highest Altitude: 10,849 feet
Largest Motor: CTI 1115J530 IM
Current Project: X Wing

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1761
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: Curing Oven questions

Postby CATO » Tue Mar 21, 2017 3:09 pm

Hi Sinful...

Close, but you have no neutral at the power outlets.

If you provide the thermostat model number we might be able to assist you a bit further or verify the wiring? Going off your pinouts I can only assume that the below would be correct.

Sinful_1.jpg
Sinful_1.jpg (57.45 KiB) Viewed 123 times


Here is the solution with the use of an additional Contactor (recommended)
Sinful_2.jpg
Sinful_2.jpg (64.54 KiB) Viewed 123 times
"In thrust we trust"

AMRS L3
AMRS Technical Advisory Group - CO

Impulse:
2017: 00,000 Ns (00.00% A)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
SpaceManMat
Astronaut
Astronaut
Posts: 1643
Joined: Mon Dec 15, 2008 9:56 pm
Location: Brisbane

Re: Curing Oven questions

Postby SpaceManMat » Tue Mar 21, 2017 4:45 pm

Good point about connecting up an earth Cato.

Do take care doing this you're making us quite nervous. Is there someone who you can take this to check it?

I'm also not an electrician either and certainly don't have any experience or knowledge of US power standards and laws.

Cato - can you talk us through the reason for the second relay? Is this just a recommendation for SSR or would you use it for a conventional relay?
QRS: 124
AMRS: 32 L2 RSO
Highest Altitude: 10,849 feet
Largest Motor: CTI 1115J530 IM
Current Project: X Wing

User avatar
OverTheTop
It's only money...
It's only money...
Posts: 2264
Joined: Sat Jul 21, 2007 2:20 pm
Location: Melbourne, Australia

Re: Curing Oven questions

Postby OverTheTop » Tue Mar 21, 2017 5:03 pm

I haven't had time to look at schematics in detail. Too busy. No rocketry since last November :( Sorry.

I was just about to post about an earth. Always think safety. Any metalwork that can be touched should be earthed. Make absolutely sure the earth from the mains is connected to the metal. If you want extra brownie points you can make sure the input mains cable is strain-relieved and that the earth wire is longer so it is the last one to be ripped out of the enclosure if you pull hard enough.

If you know someone with a mains safety tester you can check it for compliance to standards for extra confidence.

Safety first.

If you can almost reach it with your index finger then it should be below 60Vac (I think) if you want to conform to international standards.
TRA #13430
L3
"Everybody's simulation model is guilty until proven innocent" (Thomas H. Lawrence 1994)

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1761
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: Curing Oven questions

Postby CATO » Tue Mar 21, 2017 5:35 pm

SpaceManMat wrote:Cato - can you talk us through the reason for the second relay? Is this just a recommendation for SSR or would you use it for a conventional relay?


Hi Matt,

The relay / contactor can supply a higher current than the supplied SSR, or provide multiple current / circuit paths. I just do not trust those SSR's,(remember they require massive Heat Sinks for their stated current rating). I guess if you had an extra low voltage "Not exceeding 50 V a.c or 120 V ripple-free d.c." coil voltage contactor you could remove/replace the SSR altogether, but being a sparky I just utilised what I had lying around (a 240v coil contactor).

I'm not stating that the SSR is not up to the task, I'm just stating I wouldn't trust them under a high load with no heat sink.
"In thrust we trust"

AMRS L3
AMRS Technical Advisory Group - CO

Impulse:
2017: 00,000 Ns (00.00% A)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
OverTheTop
It's only money...
It's only money...
Posts: 2264
Joined: Sat Jul 21, 2007 2:20 pm
Location: Melbourne, Australia

Re: Curing Oven questions

Postby OverTheTop » Tue Mar 21, 2017 5:42 pm

What's wrong with good old electro-mechanical relays? Only power dissipation is coil, not load related. Just asking the question...
TRA #13430
L3
"Everybody's simulation model is guilty until proven innocent" (Thomas H. Lawrence 1994)

SinfulDarkLord
Rocket Flyer
Rocket Flyer
Posts: 193
Joined: Mon Oct 07, 2013 11:35 am

Re: Curing Oven questions

Postby SinfulDarkLord » Tue Mar 21, 2017 6:21 pm

Thank you guys for the assistance, this is why I ask these questions, because you guys have more experience on this.

CATO your diagram appears to be correct. I can indeed supply a ground wire, in fact the power outlet box had connects to be grounded, I will post later today.

SpaceManMat I do appreciate the safety concern and that is why I am not hesistant to wire this up anytime soon. My father knows an electrician and would be willing to help out later on. I only asked here as you guys do this more often.

OverTheTop I too am without rocketry over 3 years now. I have been making carbon tubes with the oven for people who dont want to spend a fortune and it lends a bit of a financial help on my end.

Thank you guys once again I really appreciate it.


Sent from my iPhone using Tapatalk

SinfulDarkLord
Rocket Flyer
Rocket Flyer
Posts: 193
Joined: Mon Oct 07, 2013 11:35 am

Re: Curing Oven questions

Postby SinfulDarkLord » Wed Mar 22, 2017 2:59 pm

Alright guys hopefully this will ease your concerns.

Image

Hopefully this will add some safety.


Sent from my iPhone using Tapatalk

SinfulDarkLord
Rocket Flyer
Rocket Flyer
Posts: 193
Joined: Mon Oct 07, 2013 11:35 am

Re: Curing Oven questions

Postby SinfulDarkLord » Thu Apr 27, 2017 5:43 am

Sorry I have not posted in awhile, the new oven is complete in terms of the construction. All I need now is the solid state relay. Unfortunately one that I ordered from crydom only operated under 480V AC so that didnt work.

I returned that and ordered another only to find that the seller did not put the PO box address and so I did not recieve it. I found a really nice Omron relay for a good price and now it is just a matter of waiting.

I was able to find a good wiring diagram on how to wire the relay and heating elements. You guys were right for me to utilize a ground for safety.

Image

Here is a picture of the oven.

Image


Sent from my iPhone using Tapatalk


Return to “Scratch Built”

Who is online

Users browsing this forum: No registered users and 10 guests