Packard Forum Index » V-8 (1955-56)

Quote:
It could but not sure how easy it would be to switch ground polarity with a board and solid state switching. The object was to find something off the shelf from Amazon or Ebay that anyone could buy and do a fairly simple install instead of needing to chase down a specialty item from a vendor. Since PNW region no longer advertises the ready made switch conversions no idea who still carries them and could see that being an issue if a specially made board was offered as the solution. Just felt ready made time delay relays were simpler and with the particular brand relay I tried, by changing positions of two wires on each relay, pos or neg ground can be accommodated. It would be nice to find a standard isolated contact relay with a shorter time delay than 10 seconds though.

Another consideration is space is at a premium in the box and there is a fairly decent surge current and back emf when the solenoids operate. Relays can handle both but with pure electronics would need something well protected and fairly hefty to do the switching and maybe need to fit a heat sink too.

Quote:

Keeping in mind that the current through it is only intermittent, what would you say it draws at the max?

Even an off-the-shelf device like this, which does use a little relay, is rated at 30A which I expect would be more than sufficient.

I have not checked solenoid current and doubt I can measure surge. No longer have access to decent test equipt and my less expensive meter does not respond very fast -- although the max hold function might catch it. Will try to come up with numbers at least for the steady draw in the next day or so. Doubt steady draw is more than 3 or 4 amps.

Instead of relays, a timer board might work and Riki and I looked at a few last year but at a quick look, contacts on most timer boards are actually 5 amps max and the 30 is max voltage. The timer board nomenclature is a bit confusing since most of the inexpensive timers say they are the delay off type. In my former life, timers described that way meant as soon as power was applied relay energized and when timer gets a trigger timing starts and relay turns off at the end of the time. Not well covered on the Amazon offerings is exactly what happens at the time end or what is needed to reset for the next cycle. Would almost need to get one and see exactly how it operates. Until that is done, from what I think I understand on operation don't believe that would work with what we have available in the box. At any rate, this time around I wanted something quick that did not need brain power so decided the TD relays were the easier way to go.

The stock circuit needs a delay on relay where timing starts and counts when the trigger gets voltage then relay energizes and stays on as long as there is voltage at the trigger. Needs to immediately drop out and stay off when trigger voltage goes away. In the relays I used there is no separate power supply needed. The trigger voltage powers both the timer circuit and relay.

The relays just power the solenoid switches, right? Hard to imagine they draw more than an amp.

The Bosch relays I have lying around are like 150mA to switch 30A.

Ok

Capacitor timing check.

47uf 5 seconds.

100uf in series with a 220uf gets 7 seconds..

Seven seconds delay.

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Math checks out

The 100 and 220 is 68 combined

Nice 10 per second too

This one was the 9 second relay.

100uf. Series with 220 uf.

It is at Packard specs.

High side of 6 seconds

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Spud

Thanks.

I.ll give 68uf a try.

50k trimmer.

I have it set at 6 seconds.high

Side..

Turn counter clockwise. The way I have .. I'm using pins 1 and 2.

The resistor I crushed it. Really couldn't UN solder it.

I ran across 2 more relays I bought. Years ago.
Never opened the box.

The relays work..

But there is no continuity at either

30. 87a
Or
30 87.

So I'll cut those open.

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