Kestrel Alternator Controller

[Theo]

Theodora's Kestrel alternator controller has a black button on the side. What is it for?

 

Nick

[musicman]

I have a kestrel unit. The black spring loaded button simply re-sets the unit so that it starts the charging cycle all over again from scratch.

[Keeping Up]

The Kestrel unit operates just once; it boosts the charing rate into the battery and when the trigger threshold voltage has been reached, such that it believes the battery to be fully charged, the unit cuts out and does not attampt to put any further charge into the battery until the engine is next re-started. If the unit is falsely triggered, for example by the sort of short voltage-spike which can occur when a 12-volt device is switched on or off anywhere on the boat, then the unit is rendered ineffective; pressing the button will (as Musicman says) restart the charging cycle.

 

When they were first introduced, they were the best thing around (because they were the only such device around); they are now an utterly obsolete technology and based on my personal experience of fried battteries, blown bulbs and fluorescents, and similar, I would replace it by a more modern unit such as the Adverc or Sterling controller at the first opportunity.

 

Allan

[Gibbo]

The Kestrel unit operates just once; it boosts the charing rate into the battery and when the trigger threshold voltage has been reached, such that it believes the battery to be fully charged, the unit cuts out and does not attampt to put any further charge into the battery until the engine is next re-started. If the unit is falsely triggered, for example by the sort of short voltage-spike which can occur when a 12-volt device is switched on or off anywhere on the boat, then the unit is rendered ineffective; pressing the button will (as Musicman says) restart the charging cycle.

 

When they were first introduced, they were the best thing around (because they were the only such device around); they are now an utterly obsolete technology and based on my personal experience of fried battteries, blown bulbs and fluorescents, and similar, I would replace it by a more modern unit such as the Adverc or Sterling controller at the first opportunity.

 

Allan

 

I did say I wouldn't bother coming back here but I couldn't resist this one. Is the GZ34 still available? (look it up if in doubt)

 

Gibbo

[Keeping Up]

I did say I wouldn't bother coming back here but I couldn't resist this one. Is the GZ34 still available? (look it up if in doubt)

 

Gibbo

Hi Gibbo,

 

OK, I admit it, you've got me stumped there. The only GZ34 that I know of is the old valve rectifier of that designation. If that's what you're referring to, I don't know if it's available, and if it was it would be difficult (but not impossible) to incorporate one into an alternator controller (now there's a challenge!)

 

Is there something else by that name - or are you making a point about obsolete equipment which was the best at the time (which could possibly describe the GZ34 valve, though personally I prefer the even-older 5Z4 version they were a nicer shape). If so I'm afraid it went right over my head.

 

Allan

[Gibbo]

Hi Gibbo,

 

OK, I admit it, you've got me stumped there. The only GZ34 that I know of is the old valve rectifier of that designation.

 

That's the one. You're showing your age

 

Is there something else by that name - or are you making a point about obsolete equipment which was the best at the time (which could possibly describe the GZ34 valve, though personally I prefer the even-older 5Z4 version they were a nicer shape). If so I'm afraid it went right over my head.

 

Sort of. It actually wouldn't surprise of there's a GZ34 in a Kestrel, afterall their designs are from about the same era.

 

Gibbo

[Keeping Up]

That's the one. You're showing your age

It actually wouldn't surprise of there's a GZ34 in a Kestrel, afterall their designs are from about the same era.

You're right about the age. When I started, everything was done with valves and it was just ages before I got the hang of these new-fangled "transistors". I had to completely re-educate myself to start thinking about current instead of voltage all the time. It was so much easier when they brought in CMOS, I could go back to thinking about voltages again.

 

My favourites were the old 807 and 813 valves, now there was some serious glassware to get your hands on, I used to have cupboards full of them (though they were tiny compared with the lovely transmitter valves at Rugby that you could actually unscrew for maintenance like changing the cathodes, then pump back down to vacuum and carry on using - not that I ever had any of those at home)

 

It wouldn't be difficult to design a valve-driven Kestrel, would it? The biggest problem would be that you'd have to work with such low voltages. Would it be cheating to use the little miniature valves from the portable radios, with a separate 90-volt battery? Otherwise I suppose you could use one of those little vibrator packs that went into the old mobile radio transmitters, then you could make a nice solid thermo-Kestrel with a 12SN7 and a couple of old GPO 3000-series relays.

 

Allan

[Sir Nibble]

Mercury arc rectifier anyone?