12v DC Delay Timer

H

HotRod

Guest
Can anyone tell me how to design a delay timer so that when I turn off the
car key the timer turns on my pump?

I think I can use a relay to get the power from 12v DC up to the amps I need
to run my oil pump.

I am installing a remote oil pump on my turbo car and want the pump to
continue to supply the turbo with oil for a minute or two after the car's
ignition is shut off. How can I create this?
 
If you don't mind that the pump is running all the time that your vehicle is
running, the answer is rather simple. If you only want the pump to run from
the time you turn the ignition off and then for a minute thereafter, it is a
little more difficult, but not by a bunch.

In the first case, you use a transistor (a darlington to get the base
current into the microamp range) to turn on the relay and a resistor with a
large capacitor to create a one minute time delay. Run the base of the
darlington to the capacitor through an appropriately sized resistor and
that's all there is to it.

Let us know if you only want the pump on at the time you turn the ignition
off.

Jim




"HotRod" <NoSpam@YourEmail.com> wrote in message
news:118mp6tkcu3aa03@corp.supernews.com...
Can anyone tell me how to design a delay timer so that when I turn off the
car key the timer turns on my pump?

I think I can use a relay to get the power from 12v DC up to the amps I
need to run my oil pump.

I am installing a remote oil pump on my turbo car and want the pump to
continue to supply the turbo with oil for a minute or two after the car's
ignition is shut off. How can I create this?
Click to expand...
 
OK after giving this a lot of thought it would also work if

1) Once the ignition is turned off I can have the engine Idle for another
minute. BUT here's the tricky part there are some components that are "ON"
when the ignition is "ON" but I want everything shut "OFF" except for the
engine that will run for a few minutes. So basically I need a way to keep
the power going to the engine "ON" switch (I'll find this wire) for another
minute or two while the key is off. I can't have this switch on all the time
like suggested.
 
HotRod wrote:
Can anyone tell me how to design a delay timer so that when I turn off the
car key the timer turns on my pump?

I think I can use a relay to get the power from 12v DC up to the amps I need
to run my oil pump.

I am installing a remote oil pump on my turbo car and want the pump to
continue to supply the turbo with oil for a minute or two after the car's
ignition is shut off. How can I create this?
Click to expand...
The best solution to a problem is to eliminate the problem in the first
place.
Why do you want the oil pump to run? If the turbo is not turning, what
good is the oil doing.
Can't you achieve the same thing by turning on the oil pump for a few
seconds before you START the engine?
mike

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The turbo is driven off the exhaust velocity and spins LONG after the engine
shuts down. No oil to the turbine bearings and they spall rather quickly.
Remember, not only is that sucker spinning at several thousand RPM, it is
hotter than hell from the exhaust.

Why would you turn the oil pump on before you start the engine? Once you
start the engine, you've got oil pressure from the engine driven pump AND
the turbine really doesn't start to whine in the normal idle start sequence.

Jim



Why do you want the oil pump to run? If the turbo is not turning, what
good is the oil doing.
Can't you achieve the same thing by turning on the oil pump for a few
seconds before you START the engine?
mike
Click to expand...
 
On Wed, 18 May 2005 13:20:13 -0700, mike <spamme0@netscape.net>
wrote:

HotRod wrote:
Can anyone tell me how to design a delay timer so that when I turn off the
car key the timer turns on my pump?

I think I can use a relay to get the power from 12v DC up to the amps I need
to run my oil pump.

I am installing a remote oil pump on my turbo car and want the pump to
continue to supply the turbo with oil for a minute or two after the car's
ignition is shut off. How can I create this?



The best solution to a problem is to eliminate the problem in the first
place.
Why do you want the oil pump to run? If the turbo is not turning, what
good is the oil doing.
Click to expand...
---
It's helping to cool down the turbo and keep the oil moving until
the turbo can't burn it. And the bearings, I think.
---

Can't you achieve the same thing by turning on the oil pump for a few
seconds before you START the engine?
Click to expand...
---
No.

What he wants is something that starts running the pump as soon as
he starts the engine, then keeps it running for a minute or so after
he turns the key off, but doesn't come on if he turns the key to ON
without starting the engine. Something like this:


+12-+-----------------------------------------+--------------+
| | |
| +-------+ |
| |K | O
| [DIODE] [COIL]- -|
+--O | | O--> |
| |S2 +-------+ |
| | <--O--+-------A | +--->PUMP+
| | NAND Y---A C
| [1K] +-- B NAND Y--+--[R]--B
| | | +---B | E +--->PUMP-
| GND | | | | |
| | | A--+ | |
| | +---Y NAND | |
+--O | B--+ | |
|S1 | | | |
| <--O------+----+-----------+ | |
| |+ | |
[1M][100ľF] | |
| | | |
GND>---------------+----+---------------------+---------+



S1 is the ignition switch and S2 is the starter switch. All of the
logic is Schmitt triggered and, since the current requirement for
the relay wasn't spelled out, there wasn't a lot of time spent on
its driver.

--
John Fields
 
"RST Engineering (jw)" <jim@rstengineering.com> schreef in bericht
news:118ne1qg9t4pgab@corp.supernews.com...
The turbo is driven off the exhaust velocity and spins LONG after the
engine
shuts down. No oil to the turbine bearings and they spall rather quickly.
Remember, not only is that sucker spinning at several thousand RPM, it is
hotter than hell from the exhaust.

Why would you turn the oil pump on before you start the engine? Once you
start the engine, you've got oil pressure from the engine driven pump AND
the turbine really doesn't start to whine in the normal idle start
sequence.

Jim



Why do you want the oil pump to run? If the turbo is not turning, what
good is the oil doing.
Can't you achieve the same thing by turning on the oil pump for a few
seconds before you START the engine?
mike
Click to expand...
The problem is not the turbine spinning when you turn off the engine, it
stops spinning quite fast. No exhaust gases to drive it, and an (almost)
shut throttle give a lot of resistance. (there is also a dumpvalve, so when
you let go off the throttle the turbo won't stall by routing the compressed
air back into the air intake. It's common 'tuning' to change this so it
vents in to open air, giving that hiss when the throttle is released).

The problem is that heat from the exhaust soaks into the bearings, burning
up the now stationary oil, so it will coal.

There are commercial 'turbo timers' that keep the engine running for a
minute or two, so the turbo can cool down a bit. But of course, you can also
do that yourself; what is usually recommended in the instruction manual.

Jeroen
 
On 18 May 2005 16:58:13 -0700, "GPG" <gpg212@yahoo.co.nz> wrote:

http://www.geocities.com/gpg212/turbotimer.GIF
Click to expand...
Alas.

I was on the edge of exclaiming: "way to go! - not once a 555 or PIC
was mentioned!" :)

I make it a habit of coasting to the gas pump when coming from the
highway - assuming the turbo cooled down in that period. Most times I
forget however. My turbo does not seem to mind @ 145KKM.

But then again - it is a leased car - and those are indestructible.



--
- René
 
As many have already mentioned Turbo's run very fast and very hot and it is
always recommended to let the engine idle for a minute or two when you stop
(get home). Unfortunately this isn't practical for me to sit in the car
waiting for the turbo to cool down. Despite the confusion I've caused what I
need is something that will

1) Keep the engine running for 1 - 2 minutes once the key is turned off.
2) Will only supply power to motor while the accessories are shut down. If I
have to I will separate all of the accessories to another switch that will
still need to be turned off by the "electronic device".
3) If possible I want to add a thermal switch to the "water jacket" around
the turbo so that if the switch is off (cold turbo) the engine won't bother
running for another minute. This would happen when I run around town but not
the HWY.

I'm going to have a look at the turbo timer and see if it might do what I
need.
 
HotRod pretended :
As many have already mentioned Turbo's run very fast and very hot and it is
always recommended to let the engine idle for a minute or two when you stop
(get home). Unfortunately this isn't practical for me to sit in the car
waiting for the turbo to cool down. Despite the confusion I've caused what I
need is something that will

1) Keep the engine running for 1 - 2 minutes once the key is turned off.
2) Will only supply power to motor while the accessories are shut down. If I
have to I will separate all of the accessories to another switch that will
still need to be turned off by the "electronic device".
3) If possible I want to add a thermal switch to the "water jacket" around
the turbo so that if the switch is off (cold turbo) the engine won't bother
running for another minute. This would happen when I run around town but not
the HWY.

I'm going to have a look at the turbo timer and see if it might do what I
need.
Click to expand...
timer modules can be had at appliance or air conditioning parts
houses.. Diaram is printed on the case... Simple.

--
This is an automatic signature of MesNews.
Site : http://www.mesnews.net
 
Lawrence Oravetz wrote:
HotRod pretended :

As many have already mentioned Turbo's run very fast and very hot and
it is always recommended to let the engine idle for a minute or two
when you stop (get home). Unfortunately this isn't practical for me to
sit in the car waiting for the turbo to cool down. Despite the
confusion I've caused what I need is something that will

1) Keep the engine running for 1 - 2 minutes once the key is turned off.
2) Will only supply power to motor while the accessories are shut
down. If I have to I will separate all of the accessories to another
switch that will still need to be turned off by the "electronic device".
3) If possible I want to add a thermal switch to the "water jacket"
around the turbo so that if the switch is off (cold turbo) the engine
won't bother running for another minute. This would happen when I run
around town but not the HWY.

I'm going to have a look at the turbo timer and see if it might do
what I need.


timer modules can be had at appliance or air conditioning parts houses..
Diaram is printed on the case... Simple.
Click to expand...
This project is typical of what you can expect of people who shy away
from confronting the challenge directly. The first purpose of the
accessory is to allow the pump oil to cool, so what are you doing
measuring time? I am not aware that time is the basic unit of measure of
temperature. What's so unique about a temperature actuated autonomous
control that runs the pump? It seems like those poorly designed foreign
cars have been doing that for years with the engine coolant fan.
 
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