Power-up delay for a 10-cent tuning

Hello,
A friend of mine took over my '1' account and is happy with the 'tuning' I did, which only cost 10 cents.
He finds it really annoying that this device doesn't have a power-on delay.
Has anyone ever built something with a power-on delay before, and do you have a schematic or plan for it?
Actually, something came to mind. Does anyone know if this is possible?
Okay, that potentiometer controls the power going to cables 2 and 3.
'Then you'll need to install another reed relay (between pins 2 and 3).'
'Then I need to connect the power-on delay circuit between the positive and negative terminals (WHICH PINS ARE POSITIVE AND NEGATIVE ON THE EIGHT-PIN CONNECTOR?).'
'Then I thought about a capacitor (SIZE?), which is charged through a resistor (SIZE?), and a transistor that is connected in parallel with the capacitor, so that after the capacitor charges, the transistor switches on the relay.'

DOES IT WORK LIKE THIS?

Why don't you make the tuning adjustable?

It can already be switched using a switch inside.
He doesn't want to always turn it on and off, but only when needed. It was also a former driving school car, but it has never been driven above 2500 RPM.
In my opinion, the engine is in excellent condition.
What could be the reason why he's performing so poorly?
What should one check?
How do I do that?

Hi,

suggermilk wrote:

It can be switched on or off using a switch inside. Er möchte aber nicht immer aus und einscahlten sondern nur bi Bedarf auscshalten.

Then the delay circuit during startup is sufficient; the solution using R, C, and a timer already works. If you add a diode to discharge C when the ignition is off, it will also ensure that the glow plug lamp doesn't light up repeatedly during multiple start attempts.

Ein Reed-Relais besteht aus zwei Kontaktzungen, welche federnd in einem Glasröhrchen eingeschmolzen sind. Durch ein äußeres Magnetfeld wird der Kontakt geschlossen. Eine Schutzgasfüllung vermindert Funkenbildung beim Öffnen des Kontaktes und erhöht so die Lebensdauer des Relais. Wie bei allen Relaistypen ist der Laststromkreis galvanisch vom Steuerstromkreis getrennt.

I'm not sure if there are reed relays with a built-in coil.
You can also use the RCT circuit to delay the illumination of a light bulb, then exit and attach a magnet to the reed relay. Of course, don't forget to remove the magnet when you stop the engine. It would be foolish if it fell off during an overtaking maneuver...
Why don't you use a standard relay and protect the transistor from voltage spikes when the coil is switched off by either:
- you are using a transistor with an integrated flyback diode.
- Are you connecting a diode in reverse bias parallel to the coil?

Quote:

What could be the reason why he is performing so poorly? Was müsste man nachschauen.

I have no idea. Think about what's unusual or noticeable about your car, and then check the error database.

Quote:

Wie mache ich das?

What do you want to do?

Here's another tip: If you try to spell words like " Einschaltverzögerung" the way that 95% of German-speaking residents of this country do, then the search function of this forum will also be useful. Then (maybe) other people can benefit from this thread. Therefore, I took the liberty of correcting it at least in the title and once in the text of the post.

Best regards, Rainer.

I'm sorry; that was probably not an intentional mistake on my part.
Regarding the delay, this would mean the following:
The relay is connected to points 1 and 4 of the potentiometer (from pump cable two and three).
Connect pin 2 of the relay to a positive voltage source, then connect it to a resistor and finally to a capacitor.
From the negative pole, connect a wire to the capacitor and then to the transistor.
Connect the 4-pole capacitor to the transistor as well.
5-transistor relay circuit.
Connect the negative terminal of the capacitor to either the resistor or point 1 on the relay using a 6-diode connection.

Did I understand the plan correctly?
ODER ist er so falsch?

What size capacitor would I need, and what value of resistor? What type of diode would be appropriate, and which relay do you recommend?
Was für ein transitor ist am besten geeignet oder kann ich den auch weglassen?

DOES ANYONE PERHAPS HAVE A COMPLETE CIRCUIT DIAGRAM ?

'Could you please provide the complete part numbers for all the components needed, especially the relay, to ensure it's the correct one?'

Hello, almost right.

Diode connected in reverse bias from the capacitor to the switched positive terminal.
When you turn off the ignition, the switched positive terminal should be connected to ground (I'm simply assuming this is the case; if the switched positive is just disconnected, it won't work). This will discharge the capacitor.

I'm afraid your further questions would lead us too far off track. Do you have a friend who is knowledgeable about electronics and with whom you could build the circuit?
Because if I have to write down which diode and what is the blocking or forward direction on the component, we would be writing forever.

Best regards, Rainer.

Unfortunately, I don't have a friend in the electronics field .

Well, maybe someone could send me a diagram or explain how it works in detail.

But fundamentally, what I said was correct, right?

suggermilk wrote:

ABer vom Grundprinzip war das ja richtig was ich gesagt habe.?

Yes .
For the transistor, I recommend the BC 547; for the diodes, use 1N4148.
Relay: one with a low coil current (to avoid overheating the transistor) and a small form factor (for space-saving).

The time constant, denoted by τ (tau), is defined as follows: At 1τ, the capacitor is charged to 63% of its capacitance. At 5τ, the capacitor is nearly fully charged. τ is calculated as:

Tau = R * C

The NPN transistor turns on when there is a voltage greater than 0.7V between the collector and the base.
The resistance between the positive terminal and the base of the transistor must be low enough that the current flowing through it, multiplied by the transistor's current amplification factor, reliably activates the relay.
As a functional safety guideline for a BC 547 transistor in the circuit mentioned, I would suggest a current gain value of around 200.
If the relay closes with a coil current of 50mA, at least 50 / 200 mA = 0.25mA must flow into the base of the transistor.
Power (12.0 - 0.7)V / 0.25mA = 45200 Ohms. To ensure it works reliably, we will use a 33k Ohm resistor.

With a time constant of 1 second, without a transistor, the voltage across the capacitor would be 0.63 * 12V = 7.56V after 1 second.
We only need about one-tenth (0.7V), so we'll set the time constant (Tau) to 10 seconds.

Based on the equation Tau = RC, we can calculate that C = Tau / R = 10 seconds / 33 kOhms = 303 microfarads. Therefore, we will purchase a capacitor with a value of 330 microfarads and a voltage rating of 25V.

The relay should engage after just over one second. To achieve longer delay times, you only need to increase the resistance; however, make sure that enough current still flows through the relay coil to activate the relay.

Okay, and now Ulf and my former professor of circuit technology are allowed to beat me up .

Best regards, Rainer.

Rainer K. wrote:

Okay, and now Ulf and my former professor of circuit technology are allowed to beat me up

.

Hi Rainer,

I haven't studied anything like that... I just skimmed over your last post.
Did you consider adding a flyback diode in parallel with the relay coil to prevent the transistor from being damaged by inductive voltage spikes when it is switched off?

Hi Ulf,

Quote:

I haven't studied anything like that

.
but you seem to be good at circuit design .

I suggested he use a freewheeling diode...

Best regards, Rainer.

Hello fellow mechanics,

I have a better idea than using a relay. A relay can only be on or off and switches abruptly.

How about using two optocouplers connected in an anti-parallel configuration? This would allow for tuning the circuit by adjusting the current flowing through the diodes.
Beim ALH z.B. könnte man die Dioden (entkoppelt) auch mit dem Signal des Ladedrucksensors ansteuern. Dann wäre das Tuning nur aktiv, wenn man wirklich richtig Gas gibt und der Ladedruck auch vorhanden ist. Das spart unnötige Rumrußerei. Mann kann mit Hilfe eines Operationsverstärkers den Diodenstrom linearisieren und die Ansprechschwelle dann z.B. auf einen Ladedruck von 0,5 bar einstellen. DaThe tuning would mostly be active only when driving at full throttle, so you'd use it only when needed, and drive without it in normal conditions.

What do you think about it?

Regards,

Eike.

Good idea!

eike wrote:

How about using two optocouplers connected in an anti-parallel configuration? Then, the tuning could also be adjusted via the diode current. Beim ALH z.B. könnte man die Dioden (entkoppelt) auch mit dem Signal des Ladedrucksensors ansteuern. . . .

Hi.

With that, you are already right in the middle of designing "better" analog power supplies .

It is not possible to derive a fixed boost pressure threshold from the LMM signal alone.
In a greatly simplified manner, the LMM signal, for example, at 2000 rpm and 1 bar of boost pressure should be the same as it is at 4000 rpm and 0 bar (which equals 1 bar absolute), or at 3000 rpm and 0.33 bar.

It is not possible to derive a fixed boost pressure threshold from the LMM signal alone.
In a greatly simplified manner, the LMM signal, for example, at 2000 rpm and 1 bar of boost pressure should be the same as it is at 4000 rpm and 0 bar (which equals 1 bar absolute) or at 3000 rpm and 0.33 bar .


No, no, Ulf, I'm not talking about the signal from the mass airflow sensor, but rather the signal from the boost pressure sensor. I think you wrote about it before, that it has approximately 1.8 volts at atmospheric pressure and around 4.55 volts at a boost pressure of 1.5 bar.

For the entire process to work, only a single operational amplifier (op-amp) would be needed, which would perform both the signal decoupling and the linearization of the diode current in the optocouplers.

Die Schaltung sieht wie folgt aus: Die LED des Optokopplers werden in den Gegenkopplungspfad einer spannungsgesteuerten OP-Stromquelle einbezogen. Die LEDs sitzen zwischen dem OP-Ausgang und dem -Eingang. Der -Eingang liegt zusätzlich mit einem Widerstand auf Masse. Der +Eingang des OP wird über ein paar Dioden an das Ladedrucksignal angekopplet. Über die Anzahl der Dioden läßt sich die Ansprechschwelle festlegen. Der The current flowing through the LED is calculated by dividing the input voltage by the resistor connected to ground.
You would just need to experiment to determine which optocoupler is best suited for the purpose and how much diode current it requires to fully switch on at maximum boost pressure, while ideally switching on very little at the boost pressure threshold. It's also worth considering whether the diodes used in the '10ct' tuning can then be omitted, or if they still make sense.
Does anyone know what the current is that flows through the 10ct tuning?

Let's see who will be the first to try it out and post a result.



Regards,

Eike.

I believe that Authal boxes operate on a similar principle (activating at a certain pressure level).

Not too long ago, there was a photo in a thread here showing a box installed inside the engine control unit. You could clearly see a wire running from the pressure sensor to the actual tuning box. It's likely that a threshold switch, triggered by a certain boost pressure, activates the tuning function.

joergs wrote:

I believe that Authal boxes operate on a similar principle (activation starting at a certain pressure level).

"...you're absolutely right about that. That's why the Authal Box has a hose that needs to be connected to the boost pressure."