Help with Water Pump

[alec_t]

Here's the revised Filter Pumps Power back-up schematic (FPPMk2). Still working on the 15-min timer.

 

[KeepItSimpleStupid]

I haven't been getting updates to this thread and I've had my own problems to deal with.

The boards look good. Nice an modular. And I think the modularity paid off. They almost look like Snap-track sized modules.

Joe could still go the DIN rail route.

A while ago, I did mention Depluggable screw terminal headers. That would have helped when you start replacing things and can disconnect everything in a few shots, but still have the advantage of screw terminals.

Joe, I'm going to mention Wire ferrules: https://www.newark.com/jsp/search/b...ch&Ntt=wire+ferrules&Ntx=mode+matchallpartial

These are basically thin tubes and come in insulated and non-insulated forms and sometimes different colors. They also sometimes have two-wire inputs.

They are really nice to have if you use stranded wire and terminals without "wire protectors". Wire protectors are a thin piece of metal in the block that prevents the screw from damaging the stranded wire. They are not used for solid wire.

So, it's just a thought.

Boy, this has been a real "project". Nice work, everybody!

 

[salty joe]

Thank you Alec for the new backup. I am lucky because it's a lot like the old backup that I started-I'm pretty sure it can be expanded to become the new backup.

Thanks KISS-getting a working PDM was not a piece of cake for me. Making duplicates made my life much easier. I'll be using solid strand wire. I know how the boards will be squared away. When I get there, I hope you guys like it. It'll look at least a teeny bit better than the gob of wires pic-promise.

 

[alec_t]

Hi KISS. Good to see you're still looking in on this thread. Sorry to hear of your probs. Hope all's now well.
Here's the timers schematic, Joe. I've tried to use components you probably already have in your spares box. Pumps should start up at power-up. Press the 'off' button to start the timer. Time is adjustable ~0-15 mins with the 500k trimmer/pot. I've included an 'on' button too, in case you want to stop the timer prematurely or in case the pumps don't immediately turn on at power-up (which is possible if the time the power supplies take to ramp up exceeds the power-on-reset time I've designed into the timer).

 

[salty joe]

Hey Alec, that timer looks fantastic! I'll have the switch up by the tank where it can't get splashed. A very nice finishing touch, thanks. If the pumps don't immediately turn on at power-up and I do nothing, will they come to life in 15 minutes or so?

First I'm giong to wrap up the battery backup. It looks like only one diode needs switched out-after that a few additions should do it. Thanks a million.

 

[alec_t]

If the pumps don't immediately turn on at power-up and I do nothing, will they come to life in 15 minutes or so?

Should do. BTW if you want even longer feed times you can increase the value of C3 (e.g. put another 390nF cap in parallel).

 

[salty joe]

Very good to know, thanks. Interesting amazing stuff.

 

[salty joe]

For the filter pumps power back up, at R5 could 1K8 be used instead of 1K5? Or should I order 1K5?

Or, I have a 330 ohm I could run parallel to the 1K8 to get close.
Or, I have three 100 ohm I could run parallel to the 1K8 to get 1K5.
How critical is it that R5 be 1K5?

Oops, I guess that'd need to be run in series.

 

[alec_t]

1k8 for R5 will be ok, but you should then put a 330Ω in series with R6 to make it effectively 1k33. The result will be to reduce the LED current slightly (from ~4.9mA to ~4.2mA).
(BTW, 330Ω in parallel with 1k8Ω = 279Ω......not exactly 'close' )

 

[salty joe]

Thanks for getting me hooked up with available parts.

I'm confused with a 1K8 and 330 in parallel. I multiplied 1.8 by 1000 and subtracted 330 for 1470, which is not too awful far from 1500. 1500 ohms is the same as 1K5 isn't it?

Anyway, back to the basement!

 

[KeepItSimpleStupid]

Joe:

Any resistor combination in parallel will ALWAYS be less than the lowest resistor value.

1/Rt=1/r1+1/r2+....1/Rn

so if they were 8 ohm resistors.

1/Rt= 1/8+1/8

1/Rt=2/8

Rt=4

or for your case:

1/Rt=1/1800 + 1/330

You can do the math. Hint: It's less than 330. If you did it the fractional way, you would have to find a common denominator.

 

[salty joe]

Joe:

Any resistor combination in parallel will ALWAYS be less than the lowest resistor value.

.

Ohhh, that makes sense. Thanks for the explanation. The icons are working for me again. Me and my squirrelly computer.

The battery backup is done except for the inline fuses that are on the way. Tomorrow, I'll take a couple old pumps and old PSs out to my truck and use the battery for a test run. Just to be safe, I'll disconnect the battery before hooking up our backup circuit.
Fingers crossed.

Do you guys think surge protectors would be a good idea to protect our electronics? The service to my house is underground, but we're hardly immune to a lighting strike.

 

[KeepItSimpleStupid]

Joe:

I think you would be good with a couple of "low" cost parts.

I'd protect the output of all of the the 24 VDC supplies and all of the 12 V supplies separately with ZNR's and a backwards fast diodes.

This does two important thing and they are: 1) It prevents you from hooking up things backwards. 2) provides some transient protection.

Surge suppressors are no good unless you have a warranty, but this is custom stuff. A tough one, unless you saved all of your receipts. You MUST save the purchase receipt for an Isobar surge suppressor.

With your GFCI wierdness, I would recommend these: **broken link removed**

In good respects, we have prevented the motor from creating havoc which is the way it should be.

Let's see what everyone else has to say.

 

[salty joe]

I already have GFIs wired up. It's always been my impression that anything electric that ends up in water should be plugged into a GFI.
I wired them in parallel so that when any one GFI trips, it only kills the device plugged into it. Unlike the very reasonable way a handful of receptacles in series are protected by a single GFI in my typical kitchen. I want the redundancy for the tank.

I'm not interested in any kind of warranty or guarantee, I just wondered if surge protection would be a good idea. It would break my heart right down the middle if I did not install any surge protection and I lost all the electronics. Just trying to minimize risk is all.

 

[KeepItSimpleStupid]

Yes, i know you did and each outlet would have to be protected UNLESS you put the protection at the panel (breaker box).

So, I lost track at this point, but earlier we had two 24 VDC supplies probably under two GFCI's at least. Hence two suppressors.

Now, I can't even come close to knowing the configuration with the new OEM controllers too.

The ISOBAR's are good, but I did see one fry once and the connected equipment replaced. A direct hit. The entire think was black. It was a 9 or 12 outlet model.

I can add something that's usually available from ebay that makes it even better.

 

[alec_t]

Just to be safe, I'll disconnect the battery before hooking up our backup circuit.

You also need to have the battery disconnected when setting the trimmer to get 13.8V at the charger's LM317 output.
As for surge protection, if you have any varistors left over from the PDM builds you could put a respective one across each ~20V supply output. I don't think whatever you add (unless it's pretty expensive) is going to protect against a nearby lightning strike. Looks like you and KISS have got the GFI issue sorted.

Edit: The FPPMk2 has no provision for shutting off the pumps if the battery voltage gets drained too low when running from the battery. That shut-off feature could be added fairly easily, but of course would then mean that the water would stagnate. Which is more important to you: keeping the pumps going as long as possible, or preventing possible battery damage from over-discharge?

 

[salty joe]

Yes, i know you did and each outlet would have to be protected UNLESS you put the protection at the panel (breaker box).

So, I lost track at this point, but earlier we had two 24 VDC supplies probably under two GFCI's at least. Hence two suppressors.

Now, I can't even come close to knowing the configuration with the new OEM controllers too.
.

Regular breaker in the breaker box.
For water movement there are 8 new pumps with their 8 new PS and 8 new controllers. All the new stuff is blended with 8 PDM and our controller. It looks like it’s going to be a happy marriage, it’s an outstanding combination. These new pumps really push some water.
Filtration will be two old pumps with two PDM driven by two old PS. This is where the battery backup goes.

You also need to have the battery disconnected when setting the trimmer to get 13.8V at the charger's LM317 output.
As for surge protection, if you have any varistors left over from the PDM builds you could put a respective one across each ~20V supply output. I don't think whatever you add (unless it's pretty expensive) is going to protect against a nearby lightning strike. Looks like you and KISS have got the GFI issue sorted.

Edit: The FPPMk2 has no provision for shutting off the pumps if the battery voltage gets drained too low when running from the battery. That shut-off feature could be added fairly easily, but of course would then mean that the water would stagnate. Which is more important to you: keeping the pumps going as long as possible, or preventing possible battery damage from over-discharge?

I’ll be sure the battery is disconnected from my truck for the entire test.
I have room to install a varistor on each PDM. If that offers a little protection against surge, consider it done. I’ll have to order some, but they don’t cost much.
Let’s keep the pumps running as long as possible. I’m going to get a big SLA battery. I’m also going to ask my neighbors to text me if power is lost, so I can fire up my little generator. Thanks guys.

 

[alec_t]

I’ll be sure the battery is disconnected from my truck for the entire test.

The battery needs to be disconnected from the charger (FPPMk2) too when setting the trimmer. Before you finally connect the battery, charge it up fully with its regular charger, as the LM317 charge rate is limited to ~0.6A and would take a long time to fully charge a flat battery.

I’m going to get a big SLA battery.

That will give many hours run-time, as two old pumps will be drawing ~2.2A. Hopefully mains power wouldn't be lost for more than a few hours.

 

[salty joe]

The battery needs to be disconnected from the charger (FPPMk2) too when setting the trimmer. .

Thanks for that-I did not get it beforehand.

The trimmer set the V at LM317 output to 13.8, no prob. With the two old PS plugged in, both pumps ran and if only one PS was plugged in, only that pump ran.
But with the pumps plugged in, the red LED flickered. When I hooked the pumps to my truck battery and unplugged the pumps, the LED lit up solid but only one of the pumps ran. I'm kicking myself right now because I should have switched pumps at that point.
That’s with a 1K8 at R5 and 1K and 330 ohm in series at R6.
OK, just got to looking and found that R6 was not connected to the junction of cathodes of D5 & D6, R1 and leg 1 of Q1. That's the bug-it's gotta be. Tomorrow, I’ll head back out to my truck for test # 2.

No, R6 seems to be correctly connected after all. Darn, I thought for sure I had the bug.

 

[KeepItSimpleStupid]

Hey Joe:

Something I've done before, but you have to be careful. I have a AC male cord to alligator clips that I use for testing.

If you have just a few alligator clips you can attach an extension cord to your car battery. If you happen to have a polarized plug (If you don;t BE CAREFUL) attach two wires.

Run the power via the extension cord rather than the project to the car.
If you can fuse at the car end all the better.

Verify polarity before using power from the extension cord.

Bonus: You can work inside when it's dark outside.