start/stop/retain relay control circuit

[warner]

hi everyone im looking for a start/stop/retain relay control circuit, to control a small a.c. generator for a project for college, well technically its a extras project im doing which ties into the onc course im on, any links would be really helpful, im after making a comparison for two so im able to choose and buy one which best suits my needs, and also have the advantage of being able to use it for other projects too, basically im trying to make a project that will combine all area's of my course into one project, and be able to use within my personal life at the same time for example be about to control the a.c generator i have made, as well as being able to control other pet projects for example some robotic projects as well as other operations like opening my curtains and windows at a set time for a set duration these are just examples thank you

 

[Lancie1]

You said you are looking for a "circuit", but later describe not a circuit but an off-the-shelf programmable device {which would be a PLC (more expensive more capabilities) or a programmable control relay (cheaper but fewer capabilities)}. Which do you want?

To give you help with designing a relay control circuit, you need to give us some specifications and details. A generic circuit will can not be depended on to work out-of-the-box, because not all control circuits run on the same voltage.

1. Need control circuit voltage level, and whether AC or DC. Notice that this is NOT necessarily the generator AC output voltage.
2. Need the generator output voltage, maximum current, and power, in order to select a contactor for the control circuit that can switch the generator voltage and power output.
3. Need to know if you have any experience in writing any type of logic program, computer program, or something similar.
4. Many people have a preference for a certain brand and model. Do you?

Even if you want a programmable control relay, you still must specify at least the first 2 items.

 

[warner]

my appologises, a got told my a friend of mine yesterday,that a start/stop/retain relay control circuit is basically a plc, although with it being april fools day i wasn't sure weather to believe him or not so i decided to post in here, to find out, i am looking to compare 2 start/stop/retain relay control circuits as a college assignment and also to be able to control the a.c. generator i have made , which is ac and voltage wise is it a low voltage only producing around 10/ 15 volts, although i have made a bridge rectifier to go onto the generator but want to test it without the rectifier first, so im able to use as an ac power source and d.c at maximum current is to be around 2-5 Ma
as for for 3 and 4 personally i prefer gx developer as im used to this software, i do have programming knowledge , and understand how to use and program gx developer software but im no expert,

 

[Lancie1]

I prefer GX Developer as im used to this software. I do have programming knowledge, and understand how to use and program GX Developer software, but I'm no expert.

Then you should pick out the Mitsubishi FX-series PLCs. Look for a price list and pick one you can afford but still has the functions that you want. Almost any of them will do what you have described for controlling 2 start/stop circuits.

Not all PLCs have the same characteristics. One size does not fit all uses. An important detail is the PLC operating voltage. 24 VDC is common, but some run on 12 VDC which might be desirable for you. Others run on 120 or 240 volts AC. Only you can decide.

Then the next important thing for you is the Input voltage (the voltage level that can be sent to the PLC inputs terminals. That is not necessarily the same as the PLC operating voltage. Again 24 VDC is a favorite level now, but there are others including 120 volts AC.

Then you have to make the same decision for the Outputs: what type, switching transistor or relay? What voltage do you need to switch?

I have a copy of the Mitsubishi Melsoft series GX Developer- FX version 8.25B, so I can help you with your programs, if you use the Mitsubishi brand and one of the FX models of PLC.

I should add a note about other possibilites. If price is a concern, and the brand is not important, then you could use a programmable relay (at least a dozen different brands and models to pick from) with free software, and the total package would be much less cost, but also fewer capabilities.

 

[warner]

aawesome thank you for that information well ithink your correct on the desired 12vdc, as for inputs im assuming relay would suit my needs best,
and "I have a copy of the Mitsubishi Melsoft series GX Developer- FX version 8.25B, so I can help you with your programs, if you use the Mitsubishi brand and one of the FX models of PLC." i would really appreciate that alot, atm im trying to run a few projects and assignments which quiet a few of them are inter linked, so realisitcally part of them are for assignments and the pother parts are my own projects, although i do admit when i started this course i didn't want to learn plc i didn't think i would have any use for it but since i have started i have realized there alot more useful than expected and tbh i love working with them, i have a whole list of things i want to test and try out along with projects of my own and college wise that i want to do to the best of my abillity, and so far i have found this forum extremely useful and an excellent guidance

 

[Lancie1]

...be able to control the a.c. generator I have made, which is AC and voltage wise is it a low voltage only producing around 10 to 15 volts AC.

Hmmm...That problem of a PLC or programmable relay that operates on and with low-voltage AC came up a few days ago. There are very few PLC models that will accept low-voltage AC as an Input. One of the few I know of is the Direct Logic (Automation Direct brand made by Koyo in Japan) DL-105, which will accept 24 VAC on some of its input terminals, but still not low enough to operate off your generator voltage. There are many that will accept 24 VDC as an input signal.

But that may not be a problem. It sounds as if you don't yet have anything in mind for your control voltage level, so I would suggest that you set your control voltage at 24 volts DC, and buy a 120 VAC-to-24 VDC power supply to provide operating voltage AND input and output voltage for your control circuit. Then you can use a contactor with a 24 VDC control coil to switch your 10-to-15 VAC generator output ON or OFF to your load devices.

 

[warner]

yes you are correct i dont yet have anything in mind and im looking for something i can control it with atm im just browsing alots of different things trying to find something which will roughly fit what im looking forand i will defo follow your suggestions, , and i havent seen that post atm, but i have seen other posts regarding start /stop/retain control circuits, and i have no problems with re doing or making another generator that's not low voltage but at the same time without the means or a voltage controller or some means of safety its something i know i wont build until i can ensure the safety of my family, (my little one loves to touch anything that moves, and i want to ensure that whilst my little one is awake that there is no way that any source of electricity can harm my family. hence the reason i made this generator low current and low voltage. but i am defo wanting to make something bigger

 

[Lancie1]

Just stick with your 10-15 VAC generator voltage BUT use a separate cheap switch-mode power supply to provide 24 VDC for all your controls.

You can buy a 120 AC/24 VDC Automation Direct PSB24-060-P Power supply here at this online link for about $28. I doubt if there is a better voltage option, but there may be 24 VDC power supplies available locally if you have an Allied Electronics store nearby.

http://www.automationdirect.com/adc...NO_PS,_PSB,_PSC,_PSM,_PSP_Series)/PSB24-060-P

 

[BryanG]

Hi Warner

You will probably call me names, but please learn to use 'full stops' to split text in to sentences. The way you run one thought in to the next and then in to the next without pausing for breath makes your questions hard to read. I am no kind of linguistic expert but give us a break (or period).

Bryan

 

[warner]

lancie1 thank you your help has been very useful, my sincere thanks to you.
and bryang not a problem, i am slightly dixlsiexic but sure, and i don't do calling names its childish and un-respectful, and i will try and make it easier for you guys to read no problem, btw lancie1 that link is coming up with a 404 code meaning(
AutomationDirect - Page Not Found
We're sorry... the page you're looking for does not exist.)
and thank you all

 

[Lancie1]

Try it again. If it still comes up with the "Page not Found", type in the "Power Supply PSB24-060-P" in the Automation Direct search box.

You may think it backward to select the power supply first, but really until you know the available voltage, you cannot buy a PLC and know for sure that you can hook it up. That PSB24-060 has a 60-watt 2.5 Amp output at 24 volts DC. That is not a whole lot of power and will limit your projects to low-power devices. If you can afford it, try to go up to a 100 watt output.

 

[warner]

Thank you lancie1 your a star working so going look into it all now, and feel free to aqdd me as a friend, i think your all class people, extremely helpful, and i feel honored to be apart of this forum, and if there is anything i am able to help out with the forum computing stuff etc dont hesitate to ask.
Jules