Need Help: Hi Speed Multi Relay Timer

[+Q__]

Hi everyone,

I'm primarily inexperienced in electronics, so I'm asking you guys how
I would go about accomplishing a concept of mine:

I need to build a circuit that does the following:

The circuit must run off of a 24 VDC JameCo DC Wall Transformer, Model
No. 163651. The power from this transformer will be used to provide
power to 30 solenoid units, Model No. SOL-52 at AllElectronics.com.

Here's the hard part:
I need to provide power to the solenoids in two different ways.
1) I need power to be provided to all of them at one time (the easiest
of the two.)
2) I need power to be sent to only one solenoid at a time, in
sequence, with a switching rate fast enough to go through the entire
30 unit sequence in as little as a fourth of a second.

Note: It's very important to take into acount that there should be as
little delay as possible between the time the operator activates the
sequence and the time the sequence starts.

Preferrably, I'd like to be able to choose between several durations
of operation: 1 second, 1/2 second, 1/4 second, 1/8 second.
That is to say, the times above would be the entire elapsed time of
the switching sequence, within which, each unit would be activated on
an even interval of the target range of elapsed time divided by the
number of units.

I would also like to be able to use something like an OOPic so I could
easily hard code solutions or variations to the operation of the
circuit.

So, my question is, how would I do this?

Recap:
-Runs off of 24 VDC Jameco DC Wall Transformer, Model No. 163651
-Uses 30 Guardian Solenoids, Part No. SOL-52 at AllElectronics.com
-Must have multi-functional operations of at least these capabilities:
1) power to all at once, or
2) power to each sequentially.
3) total sequenced operation times of 1/2 sec, 1/4 sec.
4) ability to be modified through direct reprogramming and
cusomization, or to be controlled via serial port.

Thanks for any help you might have,

+Q__

 

[John Fields]

Hi everyone,

I'm primarily inexperienced in electronics, so I'm asking you guys how
I would go about accomplishing a concept of mine:

I need to build a circuit that does the following:

The circuit must run off of a 24 VDC JameCo DC Wall Transformer, Model
No. 163651. The power from this transformer will be used to provide
power to 30 solenoid units, Model No. SOL-52 at AllElectronics.com.

Here's the hard part:
I need to provide power to the solenoids in two different ways.
1) I need power to be provided to all of them at one time (the easiest
of the two.)
2) I need power to be sent to only one solenoid at a time, in
sequence, with a switching rate fast enough to go through the entire
30 unit sequence in as little as a fourth of a second.

Note: It's very important to take into acount that there should be as
little delay as possible between the time the operator activates the
sequence and the time the sequence starts.

Preferrably, I'd like to be able to choose between several durations
of operation: 1 second, 1/2 second, 1/4 second, 1/8 second.
That is to say, the times above would be the entire elapsed time of
the switching sequence, within which, each unit would be activated on
an even interval of the target range of elapsed time divided by the
number of units.

I would also like to be able to use something like an OOPic so I could
easily hard code solutions or variations to the operation of the
circuit.

So, my question is, how would I do this?

Recap:
-Runs off of 24 VDC Jameco DC Wall Transformer, Model No. 163651
-Uses 30 Guardian Solenoids, Part No. SOL-52 at AllElectronics.com
-Must have multi-functional operations of at least these capabilities:
1) power to all at once, or
2) power to each sequentially.
3) total sequenced operation times of 1/2 sec, 1/4 sec.
4) ability to be modified through direct reprogramming and
cusomization, or to be controlled via serial port.

---
I think you're going to have a few problems.

1200mA/30 solenoids is 40mA per solenoid with the 24V wall-wart you've
specified. I'd be surprised if that would be enough current to pull in
all of the solenoids at once.

250ms/30 solenoids is about 8.3ms per solenoid.

I couldn't find any spec's for the solenoids, but I'd be _very_
surprised if they will fully extend and then fully retract in 8ms.

If you can solve _that_ problem, driving them with any sequence you like
is duck soup; just use four 8 bit serial-in parallel-out shift registers
with latched outputs ('HC165's, say), clock the data through the SR by
daisy-chaining their serial outputs and inputs and when you want to
update the solenoid array use latch clock to get a broadside output from
the SR. Drive the solenoids with FETS or bipolar transistors, and drive
the solenoids with the transistors' collectors/drains. Don't forget the
diodes across each of the solenoid coils.

 

[CFoley1064]

Recap:

-Runs off of 24 VDC Jameco DC Wall Transformer, Model No. 163651
-Uses 30 Guardian Solenoids, Part No. SOL-52 at AllElectronics.com
-Must have multi-functional operations of at least these capabilities:
1) power to all at once, or
2) power to each sequentially.
3) total sequenced operation times of 1/2 sec, 1/4 sec.
4) ability to be modified through direct reprogramming and
cusomization, or to be controlled via serial port.

Thanks for any help you might have,

+Q__

Since you're a beginner, you need to know Ohm's Law, which states the
relationship between voltage, current and resistance.

V = I * R, or

I = V / R

Your solenoids are 44 ohms (R). Operating them at 24V, each one that's on will
use

I = 24V/44 ohms = .54 Amp, or 540 mA. That means, for all 30 of them to be on,
you will need 16.2 Amps. Your chosen DC power supply is good for 24VDC at 1200
mA, or 1.2A. At the minimum, you need to think about how you're going to power
this thing.

Also, 1/8 second for 30 solenoids gives them 4.1 milliseconds apiece to cycle.
Even 1/4 second, or 8.3 ms, is too fast. Remember, these things have a spring
return, which takes time to work (it's a push-type). It'll probably push out
right quick, but your return time's gonna be disappointing. You can minimize
the return time by using a high power zener to absorb some of the energy at
turn-off, but the spring is still the determining factor.

Good luck. You might want to try sci.electronics.basics.