I'm new to this forum as well as trying to play with some circuits.

A while back I installed a system that automatically changes water in my aquarium. This involves three solenoid valves which I have noticed get really hot.

In order to reduce the coil temperature I have ordered:
http://hpcontrol.uk/ekonomizer-do-e...cy-zuzycie-pradu-i-nagrzewanie-cewki-177.html

They are ment to be installed between the solenoids three pin connection (DIN 43650A) and the female connector. However, my valves have a power cord from source to coil.

How can I install the device on a cord? Are there any male valve connectors out there? I can find plenty of female connectors, DIN 43650A, but no males.

 

It's a 12V DC system by the way.

 

Reading the device description and operation, the way they use the english language makes me leery they might not be such a great company. Given also that they have no reviews you have nothing to go on whether their product is good or is junk. I'd stay away from places that don't use proper english. A lot of what I read didn't make sense. One hand they start talking about their reliability and end it with negative comments about it's failure. Kind of putting the cart before the kitchen sink. Made no sense to me either. Here's the suspect text (in part): "The solenoid valves are devices which are extremely durable and not always a good solution is to use the valve actuator due to their failure. But they have one drawback - if the valve needs to be operated for a long period of time consumes electricity and heats up." See what I mean? Extremely durable and not always a good solution - - - due to their failure?

What they MIGHT be doing is allowing full current at startup then limiting current to minimize consumption and heat buildup. But I'm not the coil expert here, so I really don't know if that's what they are doing or even if that's a good approach. Bottom line, I'd keep searching for a solution. I don't think you've found one with that device.

 

It would be helpful if we could see the solenoids you are using. You mention three wires; solenoids, far as I know, have two wires. Unless you use (for instance) 1 & 2 to energize and then use 1 & 3 to sustain. Again, just guessing here. Give us as much information as you can and I'm CERTAIN someone here will be able to find a solution to your problem.

 

The link I provided is not from the actual site I bought, it just had good pictures. The device can be found in many places. From what I have understood it's function is somewhat like a resistor in paralell with a capacitor. It can initially provide the high opening current for the solenoid, and then continously provide a lower "hold current".

I have three solenoids, but each of them have its own 12V DC power source. This is the one:
https://www.electricsolenoidvalves.com/1-2-12v-dc-electric-brass-solenoid-valve/

The coil gets really hot after a couple of minutes. I've read that they keep using the full opening current unless it is limited after opening, hence my interest in this device.

My solenoids do not have the typical male connector that the device is intended to plug into.

I've been looking at Hirschmann GDM 3000: https://www.tme.eu/html/EN/square-connectors-gdm-series/ramka_1118_EN_pelny.html

- but how do i connect it to the cords from the solenoid? Is it suppose to be mounted in a GDM housing (same link)?

I'm a complete newbie and ordering this device might have been a mistake, but I don't know how to reduce the hold current without it.

 

The solenoid pictured has only two wires. If yours has two wires then I would assume (I said "ASSUME") black is negative and red is positive. Since each has its own power supply then three of those devices you mentioned can be wired in - provided they have only two wires. Unless they themselves require a power supply as well. But to be able to fully help you we're going to need a bit more detail. So far I've not seen anything on the wiring or installation of the device you've ordered. If it IS a cap and resistor then why are you spending so much? Couldn't you build one yourself and save yourself all that cash?

As for what size capacitor you'd need I'd assume it would have to be a significantly large capacitance, like on the order of 100,000 microfarads (a.k.a 0.1 farad), and a voltage (for safety margin I'd go with) 50 volts or higher. That way any back EMF won't hurt your cap. As for a resistor, depending on what the hold current is for your solenoid, I'd do the math to figure the resistance and the wattage, then I'd go with that resistance but double the wattage.

Bottom line, you're going to be wasting power somewhere. Whether it's through a hot resistor or a hot solenoid. I don't know if PWM (Pulse Width Modulation) would be of any use, you'd still have the issue of timing the start current and then keeping the hold current. PWM won't waste as much power.

And that half inch valve - couldn't you go with a sprinkler control valve? They're much smaller, and require (likely) less current. OK, they require 24 VAC, but that should be pretty easy too. 24 volt transformers are plentiful.

I suppose it might be important to know how much pressure you're dealing with in the water stream. You said it's for an aquarium, so I'm betting it's a pretty low pressure. Sprinkler control valves should handle that job nicely. And one nice thing about them - they don't slam open and closed. I'm guessing, but your valves probably are hard open and hard closed. Fish might not like that kind of concussion wave in their aquarium.

How big is your aquarium? I'm guessing it's going to be pretty big. Wouldn't be surprised if it were over a thousand gallons, given the size and number of valves you're using.

OH - another thing: If you're using three 1/2 inch valves simply because of volume, go with a single 3/4 inch valve. It's going to have nearly the same volume. OR go with a 1 inch valve and you'll have four times the volume of a single 1/2 inch valve.

 

The reason that I use three valves is simply to reduce the risk of a failure (uncontrolled filling).

Each valve is opened by a relay and a 12V timer. I'm very satisfied with the system that has worked for maybe half a year now (no more manual water changes!). Simple wiring: 12V dc source - timer / relay - valve.

The only thing I'm not fully satisfied with is the solenoid coil temperature. It will reduce the life span and I don't want a fire hazard.

I've tried to read online about how to reduce the hold current and found some good sites. It can be done cheaper than this device, but it doesn't seem as simple as one might think. One resistor in parallell with a capacitor is not enough, due to factors I barely understand (having to do with the closing of the valve and uncontrolled current requiring several resistors, diodes....).

This device is suppose to do exactly what I need, without having to study for a masters in electronics...

As you can see in the first link it does not have any wires, rather a male and female DIN 43650A on opposite sides.

My valve does not have a solenoid 3-pin connector. It has two wires (yes I know which one is +/- and how to solder).

So I would need to cut the two wires and attach a male and female DIN43650A connector. I find plenty of female ones prepared for two wires. The male connectors I find look like the Hirschmann GDM3000, but I dont understand how it's supposed do attach to the wires. Does it fit in a housing? Which one?

Appreciate your help!

 

Without having the unit in hand or a good picture of what the plug bodies look like I can't answer that question. Suffice is to say that if you can find a plug that works then great. Otherwise you might just open up the unit and install some wires where the plug sockets are connected. Then get a simple trailer plug from your local auto parts dealership - or go to a junk yard and scavenge some connectors and simply butt splice them in. Or solder them and tape or sleeve them. The option is up to your imagination.

One note: I suppose if one valve stuck open your tank would eventually over fill. Unless you have an alarm system on the line to let you know when a problem is developing. Sorry I couldn't be of more assistance in this case.

 

Maybe he is using 3 valves in series (triple redundancy). As long

 

Thank you for your involvement!

I have focused on safety first. One valve is for hot water and one for cold. They mix in a temperature control valve, and then I have my extra solenoid number three. It's therefore not enough for one valve to get stuck in order to overfill the aquarium. I also have a level sensor / relay and an overflow to drain

The part I need to connect to my wires on each solenoid is:
https://uk.rs-online.com/mobile/p/din-43650-solenoid-connectors/0486987/

Is that picture good enough? I can't figure out if it goes into a Hirschmann housing or how it is properly connected. Is it supposed to be mounted in a housing like this one?
https://uk.rs-online.com/mobile/p/din-43650-solenoid-connectors/2264341/

 

Oh. So one valve feeds hot, one feeds cold and the third feeds the mixed water into the tank. Right?

As far as the connector goes - I don't know of any convention for it to be wired. Not like a house plug or 240 dryer or 240 electric range plug. I think you wire it up however the wires are on the valve. If you have wires that are simply out there you can wire it up any way you like, as long as the mating plug is wired the same way. As for how to install your current limiter - again, however the connections are shown. Assumedly there is going to be a wiring diagram with the units. Have you gotten them yet?

 

Yes, you're right about the valves. The third one that feeds mixed water is connected to the level switch in top of the aquarium. All of them are controlled independently with dc timers.

The current limit device has a really simple connection (shown in my first link), IF you have a traditional solenoid valve with a three pin male connection. Then you just plug the device straight onto the male connection.

I don't want to unneccesarily pry open the device. The easiest way seems to attach a three pin connector (DIN 43650A) to my valve wires. It's this one:
https://www.tme.eu/en/details/gsa-u2000nlo/valve-connectors/hirschmann/933378100-gsa-u-2000-n-lo/

I've been looking everywhere to figure out how it is mounted. It must be in this one...
https://www.tme.eu/en/details/gdm2011sw/valve-connectors/hirschmann/

...but I'd like to have that confirmed. If it fits in that housing, than connecting wires safely is easy.

 

Your best bet would probably be to call the company and ask them for any specs you can't get on line. Aside from that I don't know if anyone here is going to know definitively if it will work or not (fit-wise). Call the company that makes the economizer and ask them what the correct mating plug is. That way you're more likely to get the right thing.

Good luck.

 

The only thing I'm not fully satisfied with is the solenoid coil temperature. It will reduce the life span and I don't want a fire hazard.

About solenoid valves:
"ALL Standard valves are supplied with CONTINUOUS DUTY COILS of the proper class of insulation for the service indicated on the valve. The coil temperature may become hot after being energized for extended periods, but it is normal. Smoke or burning odor indicates excessive coil temperature and should disconnect the power to the coil immediately". Yours look to be pretty standard solenoid valves. I would not worry about too much and if I did I would just add a few inexpensive 12 VDC fans as found in home computers and have them run when the solenoids are active.

As to the device? Solenoids, like relays have a Pull In voltage and current as you noted and a Drop Out voltage and current. If I apply 12 volts the solenoid will activate and draw its rated current. I reduce that voltage to just above Drop Out and the valve should remain active and the current draw reduced. That would be my guess. The product should include a "How To" or drawing or something? Less a known part number, manufacturer and some form of data sheet or instruction manual I have no idea how they (the manufacturer) expect you to connect and use the product. I would have just used a few PC fans.

Ron

 

The valves do give a burning odor after a while. They are continous duty.

I have the specs and how to connect it. Like I said it connects on a DIN43650A male. Guess I have to contact Hirschmann and ask what housing the male contacts go in.

A fan will only cool down the outside of the valve, aiding coil cooling a bit. It seems better to reduce the hold current.

The valves draw around 2amps when open but only need around 0.3amps.

 

The manufacturer answered my email, and the male connector fits in the housing as I suspected.

 

The manufacturer answered my email, and the male connector fits in the housing as I suspected.

There you go.

Ron

 

Every solenoid valve I've ever seen with the three blade connection you've shown had coil inputs on the two sides and safety ground in the middle. If your valves don't have a third wire, they must not have a separate ground wire (probably deemed unnecessary at lower DC voltages.)

I think you've got good odds of success using the outside terminals to connect to your valve wires. What I'm lies certain of is whether your power reducing device needs the ground connection or whether it's simply a pass through to feed the valve. If it's just a pass through, you could simply ignore it. If not, you'd have to run a new wire from ground to the third input on your power saving device.

Mind you, these are all just educated guesses based on limited information. If I were in your shoes, I'd do any testing and experimentation with this unknown device on a valve that wasn't hooked up to my aquarium. Either use a spare valve for testing, or simply remove one of your existing valves from the aquarium hydraulic circuit until you're certain that everything is working electrically the way you want. If you smoke a valve or the power reducing device, you've lost some money, but you'll be ok. You don't want some out of control disaster happening while you're connected to the aquarium though - dead fish, flood damage, etc.

 

Thank you for great advice!