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Electronic Relays/Solenoids

Feetwet

Active Member
I have never had much luck with mechanical solenoids, either in marine applications or in aircraft. They always seem to pit and go intermittant after a year or two's use. My RV-4 starter solenoid went out the end of last year, and now the master is intermittently chattering. Has anyone considered or tried the Cole Hersee electronic solenoid as either a master relay or start solenoid? It appears to cost about $112 and handle 85 amps.
 
I researched high-amperage solenoids for my gear retraction system (off subject, but same types of solenoids). They are much more expensive; most are not truly rated for continuous amperage, few are for high voltage DC current, and from what I have come to understand they consume a measurable portion of what they control.

Thus, you will end up losing range (e.g. they act a bit like a resistor). They can also fail, but I don't know how much more or less likely that is.

I would recommend simply having multiply redundant systems (like we do in the airplane world). Many inexpensive redundant components configured in a "system" tend to be more reliable than a single expensive component.
 
Spruce has a Lamar version for $115

http://www.aircraftspruce.com/catalog/elpages/superSwitch.php
http://www.aircraftspruce.com/catalog/pdf/superswitchconfigurationlamar.pdf
07-01283.jpg
 
Lamar vs. Cole Hersee eSolenoids

Very interesting! The Lamar unit as advertised seems to be able to replace both the master relay and the starter solenoid. When you view the Cole Hersee unit, (Part No. 48785), it looks very different and the most common application seems to be Marine. With all the cooling fins it would seem to be more designed for continuous use. I have e-mailed customer service at Cole Hersee to see if they believe 48785 is a substitute for the 24115 master relay, and the 24021 starter solenoid. I will post the reply if I get one.

The price for both Lamar and Hersee units is about five times that for the mechanical solenoids, but if the eSolenoids truly provide trouble free service for the life of the aircraft, the extra $80 is probably well spent.
 
That partially answers the power question - it lists 1.7 watt "hold power", which equates to only about 0.15 amps at 12 volts. If there are no transmission losses in addition to that (no internal resistance to the power flow) then I'd say these have matured to prime time use.

:D
 
Read the specs carefully, the units Rick has linked to appear to be a mechanical unit-----solenoid and contact points.

Not to mention it costs close to $200:eek:

Re read the first line of the OP, he is looking for a non mechanical setup, as I read this.

Something solid state. No contact points. Like what William Curtis posted, but the unit in his post is not rated enough amps for a starter.

I am afraid that if a solid state unit exists that will handle starter load, it is going to really scare folks with the price, and possibly the physical size.
 
We have several of the Lamar units that we are looking at in the lab here. You can buy them in several variations: unidirectional current flow (starter solenoid) or bi-directional current flow (master relay or cross-tie). You can also get positive trigger (starter) or negative (master).

The hold current draw is negligible, whereas mechanical contactors are about 0.7A at 14v.

Now just need to find time to put 'em on my RV... :cool:
 
Very Helpful MCA, thanks. It looks like the Lamar superswitch is a good option for my Master relay. I presume a diode isn't necessary, and understand the ground switching, but why is bidirectional necessary for a Master?
 
but why is bidirectional necessary for a Master?

Current flows out of the battery before you start the engine.

If all is working properly, after engine start, current flows into the battery.

Both cases, the current is going through the master----first out bound, then inbound.
 
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I would like to know what the on resistance specification of one of these units. Typically in switching transistors there is an on-state resistance spec (RON). Just a few milliohms here can equate to a lot of current lost to heat, particularly when starting.
 
Very Helpful MCA, thanks. It looks like the Lamar superswitch is a good option for my Master relay. I presume a diode isn't necessary, and understand the ground switching, but why is bidirectional necessary for a Master?

The battery charges as well as discharges through the master contactor. Current needs to flow into as well as out of the battery through it.
 
Thanks Guys, I should have figured the bi-directional requirement myself. I will go ahead and try the Lamar as a Master Relay, although my Pappy says: "Never buy or fly the Mark I of anything!" If I have any problems I'll post it. I never did get a reply from Cole Hersee.
 
Well, I got the Lamar Superswitch today. The mounting was an ill thought out extension of the case, with very small mounting holes, and the switch side was wired in a cheesy manner that could swivel around, pulling on the lightly soldered contacts visable on the back of the circuit board. Don?t believe the unit would hold up under normal service. Very disappointing, I sent it back and will install the standard mechanical unit.
 
Gary, thanks for the update/book report.

Sorry to hear that it isnt what you hoped for:(
 
Superswitch

I'm getting close to needing contactors for my RV-8, and like the idea of these solid-state superswitches.

I'm curious that they're being sold by AircraftSpruce but that I can't find any testimonials from users...

Does anyone have any guidance?
 
I have never had much luck with mechanical solenoids, either in marine applications or in aircraft. They always seem to pit and go intermittant after a year or two's use.

Since you've turned back toward standard units, perhaps you should consider why you are getting short service life. If you have not already done so, perhaps check out Aeroelectric Connection to read up on using diodes to protect the solenoids and extend their life. Here's a link to the website:

http://www.aeroelectric.com/

Here are three links to B&C's website with info on solenoids. S702-1 already has the protection diodes built-in.

http://www.bandc.biz/pdfs/S701-1_Wiring.pdf

http://www.bandc.biz/pdfs/S701-2_Wiring.pdf

http://www.bandc.biz/pdfs/S702-1_Wiring.pdf
 
The Tyco EV200 mentioned by Rick is hard to find. It does seem to be available in a marine version under the brand name of Blue Sea Systems. Another option are the contactors by Gigavac (www.gigavac.com). Several feature coils that only use .090 amps. The GX12 looks very appropriate and can handle starter current too. Looks like the price is about $100.

Jim Butcher
Europa N241BW
 
Time for another starter solenoid

Interesting looking back at these posts. I put in a mechanical starter solenoid and diode in 2009 (from Vans). Now 7 years later, the first indications of a starter solenoid problem (popped fuse on start attempt) has occurred again. The first solenoid lasted about 9 years. Doesn't seem to be much advance in the electronic relay area, so I guess it's back to Vans for another diode and mechanical solenoid. I suppose an 8 year average isn't too bad for $32 on a heavy use item. On another note, Bubblehead suggested the diode protected the solenoid. Every reference I've seen, even in the links provided state that the only thing the diode protects is the starter switch. So far I have not had to replace my starter button so this seems to be correct.
 
Master

Very Helpful MCA, thanks. It looks like the Lamar superswitch is a good option for my Master relay. I presume a diode isn't necessary, and understand the ground switching, but why is bidirectional necessary for a Master?

Been using one for the master for the last two years. No problems and next to no current on the control line. If there is one concern it is the minimal environmental seals. The back of my unit is open to the PC board so I had to make my own seals.
2011-11-15_15-35-07_929_zps24olbx6e.jpg

2011-11-26_09-21-20_978_zpsv1h4gj0h.jpg
 
As option, look at this solenoid:http://www.ebay.com/itm/Blue-Sea-Sy...ash=item4d41419df0:g:UAoAAOSwZ8ZW5Hmc&vxp=mtr

These are direct replacements for standard master relays. I shifted to this once I determined the current draw to keep two standard master relays (two battery set up) was about half of the total panel draw (assuming landing lights, pitot heat and such are off).

The 0.13amp holding current as well as the high quality are the selling points.

I have two of these flying in my RV-10. Five of these are in the Lancair 4 that just did the around the world run over the poles (three alternators, three batteries and cross ties). No issues with either install.

Carl
 
BlueSea

Went to the BlueSea site, and checked out the 9012. Looks like high quality and high amperage handling, but from the shape and reference to a coil in the specifications I suspect it is still a mechanical unit, although a sealed high quality one. I am sure it is great for Marine applications, because salt water is **** on the iron solenoid throw. It is probably good for many more cycles than the standard Vans or ACspruce units. It should also be good for either master or starter solenoid, and physically fit in as a replacement. Guess it comes down to personal cost benefit analysis: cost is ~ 8 times the cost of the Vans unit and twice the cost of the high quality ACspruce units, benefit is reduced number of change out of the solenoids, and less chance of master or starter crapping out when badly wanted! The Cole Hersee units may still be the best option if you have the space and $$s although they have less amperage handling capability, but it would be an experiment. The 48765 is ~3x3x6".
 
Went to the BlueSea site, and checked out the 9012. Looks like high quality and high amperage handling, but from the shape and reference to a coil in the specifications I suspect it is still a mechanical unit, although a sealed high quality one. I am sure it is great for Marine applications, because salt water is **** on the iron solenoid throw. It is probably good for many more cycles than the standard Vans or ACspruce units. It should also be good for either master or starter solenoid, and physically fit in as a replacement. Guess it comes down to personal cost benefit analysis: cost is ~ 8 times the cost of the Vans unit and twice the cost of the high quality ACspruce units, benefit is reduced number of change out of the solenoids, and less chance of master or starter crapping out when badly wanted! The Cole Hersee units may still be the best option if you have the space and $$s although they have less amperage handling capability, but it would be an experiment. The 48765 is ~3x3x6".

The sole reason I use the Blue Sea units is the very low holding current. Compared to standard master relays, this almost doubles the reserve battery power available to the panel if your alternator fails - for me the battery reserve typically exceeds fuel range.

Carl
 
New Vans Starter Solenoid, ordered BlueSea for Main

Carl,

Followed your lead and ordered a BlueSea 9012 to use as main solenoid. Not an exact physical replacement, the large terminals are oriented differently, but should fit with minimum rework. I like the low holding voltage because I have a minimum system with a B&C alternator, and also as you mentioned for battery time with alternator failure. For the time being, replaced the starter solenoid with a standard Vans unit and new diode. Noticed later that the red Cole Hersee 24213-01 might be a better unit for only about twice the cost. Apparently the -01 notation means the coils are potted for vibration resistance.

Noticed in another thread on this forum that someone is having a problem with the Lamar solenoids apparently passing some voltage thru in the off position on the large terminals.
 
Carl,

For the time being, replaced the starter solenoid with a standard Vans unit and new diode.

I still use the standard Van's starter solenoid. For such intermittent duty it is just fine - and I saved a few dollars for the avgas account.

Carl
 
I have been looking at replacing one of my two Cole-Hersee contactors with a InPower SSC20-200 solid state contactor. The spec'ed on resistance is 0.75 milliohms, which translates to an interesting derating from 200 amps continuous to 125 amps based on the mounting. You get the full rating if it is attached to a 16x16 piece of aluminum and the 125 amp derating in free air or on a plastic/wood mounting surface. Looks to be designed for high in-rush current and inductive load spikes associated with starters. Not cheap at $130, the 100 Amp version is available at $84.

With one of each type, I should be able to get a good A-B comparison on total heat dissipation during operation.

John Salak
RV-12 N896HS
 
BlueSea 9012 installed and Ops Checked

Got the BlueSea 9012, turns out it's actually built by Gigavac and called the Gigavac GV200. Here is a link to the specifications: http://www.gigavac.com/sites/default/files/competitors/gv200.pdf

Installed it in my RV4, while retaining the ability to revert to the Van standard main battery relay. The specifications said it has internal coil suppression, (do not recognize the symbol in the diagram) so did not use a diode. The Unit has wires for the control coil instead of terminals, so I installed a double terminal block next to it and connected the wires. Initially screwed up the wiring and it didn't work. Turns out the Van's relay control coils have one side of the coil connected internally to battery plus, so the single control coil terminal just has to be connected thru the battery switch to ground. The new unit has red and black control wires and the control coil is not connected internally, so the red wire has to be connected to battery plus, and then the black wire can be connected through the battery switch to ground same as the van's standard relay.

Ops checked OK, pulled 4 "g"s and it didn't drop out. If something goes wrong will post an update.

One other reason for my installing it besides lower control amperage and hopefully greater reliability. In my RV4 it is installed below the glovebox, between my legs. The fuel line, boost pump and gascolator are also in there. I like the idea of a hermetically sealed solenoid when it is enclosed close to the fuel line.
 
Terminal Blocks

One other item may be of use to builders: I used a standard #10 (10-32) double terminal block next to the solenoid from local electronics shop, but I didn't want to use the screws since access with a screwdriver was limited. So I drilled out the back below the screws, ran longer stainless screws in from the opposite direction and locked them with a nut. Presto, with another nut I had terminal posts. Make sure you use rubber caps if not a ground.
 
Presumed Bad Battery Master Switch

So something did go wrong. Stopped at Weed on my way from Tucson to Seattle. After refueling tried to switch the master on, Nothing! After several further attempts, it finally turned on. Worked OK when I got back to Seattle. The switch was old, but only 4 or 5 flights since I changed out the solenoid, too much of a coincidence. I decided to change the battery switch, and install the yellow Vans diode on the solenoid. The Vans diode instructions are:
SolenoidDiodeSmall.jpg

But why the difference between diode wiring for the starter and the master solenoid, and what about my master solenoid which has two control terminals? I researched a little further and came up with the following.
3coil.jpg


The key is that the master solenoid is switched on the ground side, and the starter on the battery side, the red bar on the diode wiring has to go toward the battery. I have installed it, hopefully it will all work fine now.
 
BlueSea solenoid works for me

OK, after three months, still working as expected, no repeat of the Weed incident. I seem to be getting an effective extra 1 amp into the system, which for an 8 amp BC alternator is significant, so I consider a BlueSea battery solenoid to be a very good idea and will retain it.
Here are the above links as images:
3coilC.ppt


SolenoidDiodeSmall.jpg
 
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