jharrell
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Re: Here we go again yet another Trombetta "Big Boy" failure!
Blue Sea, buy once cry once. Used them on boats in salt water, when I got my RV and had the cheap trombetta go out I replaced with: https://www.bluesea.com/products/category/35/91/Automatic_Charging_Relays/ML-ACRs. Its bistable with hysteresis so no chatter under any condition, silver plated contacts rated at 300 amp live switching, 500 continuous, 700 for 5 minutes and 1450 for 30 second cranking. It detects charging voltage on either side and engages in auto mode (so alternator charges house and shore charges starting) or the switch can be set manual on or manual off. Switch has a light letting you know its engaged. Direct replacement using same wires for combine switch that was already there (had to run extra wire for status light)476Views0likes0CommentsRe: shutting down generator with air conditioner running
pianotuna wrote: They are powered by the inverter. But if you turn off the inverter the fans cease to run. Or, if 120 volt shore power is being used to charge the battery bank via the Magnum, is disconnected, the fans also stop running. The inverter is either running forward inverting making 120v or running in reverse charging using 120v. If it is doing neither than there is no need to actively cool the fets or transformer. The inverter has temp sensors on the fets and transformer, it will run the fans based on temp alone so long as it has at least 9.5v at the battery terminals: From the manual: The inverter contains two internal cooling fans that are automatically controlled. The speed of these fans is determined either by the internal temperature of the inverter or by the load on the inverter. The inverter’s fans will come on under the conditions listed below: • Fans run full speed if the internal transistors (FETS) or the power transformer reaches 176°F (80°C), or the inverter is running at 100% of its rated load. • Fans run medium speed if the internal transistors (FETS) or the power transformer reaches 140°F (60°C), or the inverter is running at 50% of its rated load. • Fans run low speed when the inverter is running at 25% of its rated load. The fans shut down if none of the above conditions are met, or if the battery voltage is < 9.5V. Whenever the inverter is first connected to the battery, the fans start for about one second.781Views0likes0CommentsRe: shutting down generator with air conditioner running
Sam Spade wrote: pianotuna wrote: The cooling fans on my inverter are AC motors. Turn off the inverter, and you turn off the cooling. That is why it caught on fire. Wait a sec. here........... Isn't the inverter supposed to produce AC power ? Why would the cooling fans NOT be powered by the inverter itself ? Am I missing something here ?? You are not missing anything, they are 12v dc fans lookup Magnum Inverter 44-0004 for the replacements, they do not run off 120v ac directly and do not require the inverter section to be on.779Views0likes0CommentsRe: Voltage drop on inverter
MEXICOWANDERER wrote: One positive One negative Excellent practice This is why I despise unsoldered lugs Don't give a **** if they're squeezed till they fart, this would never happen with soldered lugs. Oh they look good Tighter than hell But it doesn't work There is ZERO protection between the interior of the lug surface and the stranded wires. I disagree and prefer crimping, these people explain why: https://www.evdrives.com/category_s/4013.htm In the marine world crimping is preferred due to oxidation and soldering can prevent flex at the lug joint as well leading to fatigue.398Views0likes0CommentsRe: air conditioner without and with autoformer
Make sure Magnum shore setting amps correct, you should have noticed it, but Magnum could be trying to charge batteries and run a/c, lowering shore amps tells the charger to back off, also tells it when load support kicks in on hybrid. Autoform and generator really not a good combo, if gen can't provide voltage auto form pulls more current, dragging gen down even more. Gen should be throttling up to provide correct voltage and current up to its capacity otherwise something wrong with it.664Views0likes0CommentsRe: Microair vs Hyper Engineering?
philh wrote: Does an autoformer have the ability to start an AC unit when running on a 2000 watt generator? I am not sure how an autoformer would help, it increases voltage by increasing current on the input side, so your locked rotor current draw just went up on the generator. In the end power is the same, the voltage sag is due to the large amount of in-rush current to the motor. A soft starter like a Easy-star ramps up voltage slowly to motor limiting current in-rush. Would be interesting to know how a autoformer can help the situation, it actually seems like it would make things worse by drawing more current from the generator. BTW My Easystart works great on my Coleman 15k.1.7KViews0likes0CommentsRe: Victron/lifeblue system 99% functional except
Make sure the temp monitor is on the right battery post, the only diagram I can find for the lynx shunt shows it on the positive post (from am solar): https://static1.squarespace.com/static/562bc73de4b0908330f67ee0/t/5bcf960c08522908f02ec2b0/1540331027603/60-VTLNX.pdf My Magnum temp monitor didn't like being on the positive post but thankfully did no damage, the manual showed it being on the negative. One thing I don't like about Victron is their documentation, Magnum has them beat here, can even find a manual to the Lynx shunt from Victron.672Views0likes0CommentsRe: Deep Cycle Battery Charging From Alternator
MEXICOWANDERER wrote: And do not forget to add the effects of the starter solenoid itself. A large field collapse can definitely be felt. It is a magnetic servo as well as electric contact controller. This seems to be mostly what is found when talking about any kind of spike from starting due to anything powered off the starter switch during cranking and would be the same with a loaded or unloaded starting motor. Instead of a flyback diode on solenoid it seem a starter relay is used to drive solenoid and that relay may have built in diode, but its even smaller coil too. I would imagine in cars with remote/push button start there is transient protection on the solid state circuit controlling the starter relay. I don't know maybe modern starters have flyback diodes since they are so easy to add but no one seems to talk about it or care the main issue seems to be arcing and RF not giant spikes like you would see from a load dumped alternator. Definitely want to get a scope on my starter system and see how large the spike is at different point to see how well my batteries suppress it.774Views0likes0CommentsRe: Deep Cycle Battery Charging From Alternator
MEXICOWANDERER wrote: The gentleman that demonstrated max observed voltage as never reaching 30 volts. Well guess what, power avalanche rectifiers are rated 28-32 volts. And no way in hell is an automobile rotor coil as large an inductor as a five pound starter motor armature. Yes but a starter motor has something a alternator doesn't, a large solenoid that breaks the circuit. Also an alternator has something a starter doesn't, a large ICE driving it. How are you going to get a large spike from the starter motor through an open solenoid? Same with the solenoid coil as its cut by the ignition switch or starter relay. Again might get some arcing and small spike as the solenoid opens but otherwise how is it going to complete the circuit? Put your finger on the wire from solenoid to starter, yeah you complete the circuit whoopee. Disconnect the battery with the alternator going full blast and the entire cars electrical system is the load dump from the engine driven alternator output for half a second.774Views0likes0CommentsRe: Deep Cycle Battery Charging From Alternator
MEXICOWANDERER wrote: If transient voltage events are rare and of little consequence why has General Motors, Nippondenso, and other manufacturers spent hundreds of millions of dollars converting all power rectifiers in their alternators from standard silicon to TVS snubber avalanche 28-32 volts? GM did it in the late 1980's. They also redesigned the 1116411 voltage regulator, then the 425 then the 437. Each update included one more TVS. Was it a mistake? All the avalanche and TVS devices? I thought this was for load dump protection if the the battery where disconnected from the alternator while running, this is where you get 120v spike right into the rest of your electrical system. This is like worst case situation, where someone was nots smart or something really bad happened like loose battery contact. with a starter motor you have the solenoid breaking the circuit, and on the coil of the solenoid you have a more likely TVS issue because you might have something sensitive after the ignition switch, but not usually. Otherwise both the ignition switch and solenoid are opened up and you get some arcing on the contacts without flyback diodes and a little spike that the battery easily absorbs before it gets back to the DC bus. This isn't my area of expertise, but not sure where you see big spikes like your talking about. I mean yeah put your fingers between solenoid and motor, but how does it jump solenoid other than arcing? Is it because it pulling down voltage on negative side? Can't really find anything on that, and it doesn't seem like TVS diodes are used on starters and ignition coils that much, but some people add them, and it seems mainly to reduce arcing to keep contacting lasting longer and maybe reduce RF.774Views0likes0Comments
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