relays,contactors, PLC's etc

[yamaha_1fan]

Sorry, yam..yeah I need the hammer. What could I have possibly been thinking to tried to clarify something. Especially when you have such a good handle on this.

badugi, the real beauty of a controller (such as the AB PICo and other families) is the remote capability. One can easily monitor and control their grow remotely with a cheap set-up. That won't be done with relay logic.

On the slim chance that someone else might be reading this thread and could possibly have some confusion as to what we are talking about....

I wasnt trying to be a dick. I was just stating I already knew what the abbreviations stood for, I just wanted an explanation of the terms.

 

[yamaha_1fan]

http://en.wikipedia.org/wiki/Switch

Down a little bit is a chart with basic explanations and circuit diagrams. Think it cleared it all up for me.

So technically we could have as many poles as we want in theory? I know there may be a physical limitation

Looking at the circuit breaker, why is it double throw? Its not switching from one load to another. Its just on/off

 

[hoosierdaddy]

Your dryer will probably be 220voltAC powered, and the breaker in the box will be a DP/DT using two 110vac's to provide the 220vac. Needs to have both of them (110's) thrown at once, as they are essentially the same circuit.

 

[yamaha_1fan]

Your dryer will probably be 220voltAC powered, and the breaker in the box will be a DP/DT using two 110vac's to provide the 220vac. Needs to have both of them (110's) thrown at once, as they are essentially the same circuit.

Yeah I figured all 220/240 breakers are DP/DT because both sides need to be disconnected at the same time. So in this instance, double throw means throwing both breakers at once.

But on a relay or contacor, double throw means it is throwing the power from one load to another. Kind of different than the circuit breaker.

SP/DT

DP/DT

I am not trying to argue, just understand why the same term is used for two different types of operation? Or is it just that the term DT is applied differently between breakers and relays?


Thanks Daddy

 

[green_tea]

http://en.wikipedia.org/wiki/Switch#Contact_arrangements


in case you are curious on the other ones out there.. (though i doubt there would be any use for what we are doing)

edit: relays: http://en.wikipedia.org/wiki/Relay

 

[badugi]

Remote capability can be had for 3 digits, as simple as a remotely controlled power strip / outlet. You don't need PLC's for this functionality. Try pricing out a PLC based system for switching multiple 1000w ballasts, and you'll cry uncle.

It's funny how on my last thread most of the same people were bashing light movers and "proving" how useless they were, without a single second of experience with them (i.e., they've never used one, never seen one used in a real grow), and how money could be better spent on other things. Is this one of those "better things" that money can be quickly, easily, and unnecessarily wasted on?

 

[Azeotrope]

I started with used parts and here is my controller for now. The box with the board and transformer and relays was a used electrical cabinet and like everything else industrial waste recylcled/reused. I mounted and wired all the components, programmed it with the lap top (just easier that way) and off we go.

 

[hoosierdaddy]

Remote capability can be had for 3 digits, as simple as a remotely controlled power strip / outlet. You don't need PLC's for this functionality. Try pricing out a PLC based system for switching multiple 1000w ballasts, and you'll cry uncle.

A controller can be had for the same money, and you would have loads more capability.
Try monitoring with a PC using your power strip turner on'er.

 

[badugi]

What exactly do I need to monitor? To see if my lights are on?

I require neither PC nor remotely controlled power strip. All I need, and use, is a digital timer and a couple of contactors. Cost me way under $100 including expensive receptacles.

And you people say I have too much money for getting a light mover (which pays me $$ every harvest)... and not this fancy toy (which I have to pay lots of $$ to gain 0.00 grams @ harvest).

 

[mandala]

yamaha- I am in the same situation as you. I have a chhc-1 (great product btw) that I would like to hook up to my 240v window ac. The thermostat seems to work ok on the ac, but I feel like conneting it to the chhc-1 would allow more precise control.

In general, I have growroom electrical skills on lock, but the stuff in this thread is way over my head. The solution to this problem is easy though. You just need one of these:
http://www.grainger.com/Grainger/items/5X847

You want a coil voltage of 120, because your trigger cable coming from chhc-1 provides 120v. My setup will use a 30 amp relay like the one shown, but my ac is really only needs 20 amp 240v.

Here are some helpful intructions on how to setup these types of relays:
http://www.hydroponics.net/learn/grow-light-controller.asp

If you dont want to build anything, just buy one of these:
http://www.horticulturesource.com/product_info.php/products_id/4852
same components, just costs $100 more!!!

 

[hoosierdaddy]

What exactly do I need to monitor? To see if my lights are on?

Well, with a PLC and the proper schematic, you could not only monitor your lights situation, but anything and everything else related to the grow.
You could monitor the water temps, air temps, EC, PPM, etc...as well as be able to manipulate each and every item you are monitoring.
Need to take a look at the grow? No problem with a web cam set up in the logic.
Need the grow to call you when one of the parameters you set has been violated? No problem...it can call and alert you to a situation via your cell phone.
The options are almost limitless with the right equipment.
And a person who did have this set up, would sure be one to laugh at, yes?

 

[badugi]

With the proper schematic you can do the same thing & more on any type of system, but sorry you're making a really weak point. I mean, if you really wanted to hire an engineer to make your cell phone also toast bread, it's very possible to make it do so...

 

[green_tea]

a taste of the DB im working on:

[18:01:15][12/1/08]W1Temp=;W2Temp=;A1Temp=;A2Temp=;A3Temp=;A4Temp=;PPM1=;EC=;FR1=1;FR2=0;VG1=1;MOM1=1;Pump1=;Pump2=;Pump3=;Pump4=;Pump=5;Pump6=;Pump7=;Pump8=;Nut1Pump=;Nut2Pump=;Nut3Pump=;Add1Pump=;Valve1=0;Valve2=0;Valve3=0;

that line every 15 seconds...

though at this point im debating on if i should switch it to more of a state based DB, so instead of polling everything every 15 seconds, it just waits until a change happens and records that... (save a lot of space / IO)

 

[hoosierdaddy]

My point is not weak, badugi. Fully functional controls are available for very cheap.

See, what an engineer did was take your archaic set-up and made it toast bread, and you are arguing that your model makes more sense.
If you have no interest in this type of thing, why are you posting here in the first place?

Now, who's points are weak here? Let's review....

 

[freeradical]

I feel like I've read every thread about flip flops and relays/contactors. If I wanted to flip flop a 1000w light, which contactor am I looking for? I do not understand the whole thing behind coil voltages, what is that? Do I need only one contactor for two lights? Can someone link me to a contactor suitable for flip flopping a 1000w light, please?

 

[badugi]

Grainger # 5X847

You can get a lower amperage rated one for a little less, but why bother. This is future-proof and "extra safe".

 

[freeradical]

Can use a SPDT relay and use the same common for both coilOn and coilOff? Can I use a relay rated for 15a for a 1000w? Is the coil voltage the voltage coming from your timer? How do I know if a given relay can handle the load of a 1000w, is it just the ampere rating? Is voltage not a limiting factor? Thanks!

 

[badugi]

I'm far from an electrician and know only enough to get by, so someone else should answer the first question for sure. (If my [probably incorrect] understanding that the neutral wire carries no current and serves no purpose on a 110/120v circuit, then a SPDT relay would work. A 15A rated relay will work for 1000w, but it'd be wise to over-size it a bit more. (Reasoning behind this is that many [digital] timers have relays rated for 15A, but sometimes fail on 1000w's due to heat from the continuous high load.)

Coil voltage is the voltage from your timer, most likely 110/120VAC (if you're in the US).

 

[freeradical]

DPDT relays are for when using two difference batteries/electric sources. This is an SPDT relay, which should be good for a flipflop, right?

 

[yamaha_1fan]

DPDT relays are for when using two difference batteries/electric sources. This is an SPDT relay, which should be good for a flipflop, right?

You will need a DPDT not a single throw.

Remember, you are switching the ouput of the ballast, not the power to the ballast. Your cord to your lamps have two wires, maybe three with a ground? You need to switch both wires. Obviously the ground does not have to be switched.


SOMEONE JUMP IN AND CORRECT ME IF I AM WRONG