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SAMLEX PST-600-24 DC-AC INVERTER PURE SINE WAVE 24VDC IN 120VAC OUT 600 WATT...

2Big2B

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SAMLEX PST-600-24 DC-AC INVERTER PURE SINE WAVE 24VDC IN 120VAC OUT 600 WATT...
Can two of these be run in parallel?

SAMLEX has a good reputation here and it looks like these are showing up as military surplus for around $100. A helluva deal me thinks...

But 600 watts is a bit light if I want to run a microwave. My intended use would be for emergency power for power outages - and it would justify why I have a couple of lifepo4 24v 100ah diy spare batteries for my power wheelchairs that I replaced. (I took advantage of a Power Queen sale for a better built pack...)

I live in an apartment - not a solar application. This might give me cheap, reliable emergency short term 120watt power if that works.

Do-able?

- For the price it might be worth picking up one anyway, even if it is only 600 watts. Not sure how usefull it would be, but it might be good for something during a power failure...
 
Best place to start is the manufacturer's manual:


See 8.5

Nor are there instructions for HOW to connect them in parallel.

A note about microwaves: 600W is not "a bit light" to run a microwave. Microwaves use 60% more power than their rated output, and in most cases, setting to lower power means a reduced duty cycle, not reduced power consumption, i.e., "50%" setting on a microwave runs the microwave at 100%, 50% of the time.

There are a few exceptions with "inverter" microwaves. Panasonic makes a model or two. They are still no more efficient than standard microwaves, but they do actually run at reduced power. With a 600W inverter, you'd likely be limited to no more than 30% power on the microwave, and this would still be crazy inefficient due to still consuming 1.6X the output.
 
Thank you for that. Other than an old cheap useless 150watt 12v car inverter, this is my first interest in looking for a reliable, budget, pure sine wave 24v inverter. So, I am trying to make sense of it all.

24v, because I have a couple of 24v 100ah diy packs handy. And 24v is more efficient.
Pure Sine Wave... Flexibility. I don't want a modified Sine Wave with all its limitations.

Looking over the specs in the manual that you were kind enough to link, I now am wondering if I can even use my 100ah lifepo4 battery packs which might overload this inverter somehow. If I am reading it right, the 24v input current maxes out at 40ah (???). Is that a problem?

Then there are all of those high wattage, high frequency Chinese inverters on ebay and Alibaba. I am sure most of them are junk, but for my use being for a potential, occasional power blackout, I probably do not need the best. But it is confusing and exhausting to try to investigate them all as I look for the exception to the rule. Wishful thinking I guess.

That SAMLEX PST-600-24 inverter is said to be high grade, and under priced due to the military surplus hitting the market. I really probably need a minimum of 3500 watts to cover any eventuality. I use direct 12v battery power to run my led house lighting, 12v fan and my cpap.

I hardly really need an inverter. But as Carrington I write this, we are getting some intense sun flares and magnetic storms. Then there is the upcoming hurricane season here in the virginia tidewater. Add to that the paranoia of a terrorist attack on the power grid, I would sort of like to have the illusion of a plan - to at least be able to cook food and maybe watch broadcast tv if possible. If I could I would build a small solar power project, butI live within the confines of an apartment with all of its restrictions.

So, I am exploring my options with a budget dictated by high rent and a small monthly Social Security check.


Any suggestions?
 
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While you can’t run a pair of 600 watt inverters in parallel, you can run them separate but io the same battery. One could provide power for a few lights, laptop computer, maybe a cable box or cable/DSL modem. Use the other one for a tv if its power requirements are less than 600 watts. A 100 ah battery will give you a few hours but you’ll need to conserve power since you don’t have any way of charging them without the grid. For cooking or heating canned foods, you’ll get much more bang for the buck with a small butane burner. Think of this as a camping trip without the mosquitos.
 
Thank you for that. Other than an old cheap useless 150watt 12v car inverter, this is my first interest in looking for a reliable, budget, pure sine wave 24v inverter. So, I am trying to make sense of it all.

24v, because I have a couple of 24v 100ah diy packs handy. And 24v is more efficient.

This is not true as an absolute. 24V allows the use of smaller conductors.

Looking over the specs in the manual that you were kind enough to link, I now am wondering if I can even use my 100ah lifepo4 battery packs which might overload this inverter somehow. If I am reading it right, the 24v input current maxes out at 40ah (???). Is that a problem?

Doesn't work like that. Each 120VAC power outlet of your home can supply at least 1800W of power, but you don't think twice about plugging a 10W light bulb into it.

Same thing with the inverter.

Besides, what I'm reading is that 40A is the maximum input current. 40A * 24V is 96W

Then there are all of those high wattage, high frequency Chinese inverters on ebay and Alibaba. I am sure most of them are junk, but for my use being for a potential, occasional power blackout, I probably do not need the best. But it is confusing and exhausting to try to investigate them all as I look for the exception to the rule. Wishful thinking I guess.

Quality is a mixed bag, but some are better than others. One thing of concern is they all have high idle consumption and low efficiency.

That SAMLEX PST-600-24 inverter is said to be high grade, and under priced due to the military surplus hitting the market. I really probably need a minimum of 3500 watts to cover any eventuality. I use direct 12v battery power to run my led house lighting, 12v fan and my cpap.

There's nothing wrong with having more than one inverter. This unit would likely do very well to efficiently run a handful of lower power items. You can even connect multiple inverters to the same battery.

I hardly really need an inverter. But I write this, we are getting some intense sun flares and magnetic storms. Then there is the upcoming hurricane season here in the virginia tidewater. Add to that the paranoia of a terrorist attack on the power grid, I would sort of like to have the illusion of a plan - to at least be able to cook food and maybe watch broadcast tv if possible. If I could I would build a small solar power project, butI live within the confines of an apartment with all of its restrictions.

Making heat with batteries is a bear. I would take that off the table and look for a fuel burning camp stove/grill for grid-down cooking.

So, I am exploring my options with a budget dictated by high rent and a small monthly Social Security check.

Budget limitations are tough for a project like this. It's best to start with a very specific goal, e.g., I want to power this, this and this for X hours per day and then design a backup system around it.
 
Looking over the specs in the manual that you were kind enough to link, I now am wondering if I can even use my 100ah lifepo4 battery packs which might overload this inverter somehow. If I am reading it right, the 24v input current maxes out at 40ah (???). Is that a problem?

NOT a problem at all. Batteries don’t push current, devices pull current is a simple way to look at it.

Edit: Eggo beat me by a few seconds with a more complete answer 😞.
 
And Samlex is a good manufacturer who really pays attention to RFI mitigation, which is important to hams like me.

Can I ask where you are finding these ?
 
While you can’t run a pair of 600 watt inverters in parallel, you can run them separate but io the same battery. One could provide power for a few lights, laptop computer, maybe a cable box or cable/DSL modem. Use the other one for a tv if its power requirements are less than 600 watts. A 100 ah battery will give you a few hours but you’ll need to conserve power since you don’t have any way of charging them without the grid. For cooking or heating canned foods, you’ll get much more bang for the buck with a small butane burner. Think of this as a camping trip without the mosquitos.
Per my lease, I am not allowed to have so much as a candle, much less a small butane burner!

I have an old small 900 watt microwave that I would try to use.
Else, I have an electric rice cooker and a crock pot can probably make do with.

I could also raid my two power chairs for a total of 4 lifepo4 24v 100ah batteries. That is a decent emergency power supply that could make last for days if I were conservative and only used the inverter sparingly.
 
NOT a problem at all. Batteries don’t push current, devices pull current is a simple way to look at it.

Edit: Eggo beat me by a few seconds with a more complete answer 😞.
Good answer about how current is being limited by the inverter's pull. Thanks.
 
And Samlex is a good manufacturer who really pays attention to RFI mitigation, which is important to hams like me.

Can I ask where you are finding these ?
Good point about the low RFI.

Not to give away my fishing spots, but they are starting to show up on ebay.

BTW, my callsign: N2MZN

..-.. ..-.


da da duh da da. da da duh da!

😎 CQ
 
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Per my lease, I am not allowed to have so much as a candle, much less a small butane burner!

I have an old small 900 watt microwave that I would try to use.
Else, I have an electric rice cooker and a crock pot can probably make do with.

I could also raid my two power chairs for a total of 4 lifepo4 24v 100ah batteries. That is a decent emergency power supply that could make last for days if I were conservative and only used the inverter sparingly.
Check Amazon for 500 watt hot plate. Lots of choices. You will chew up a lot of battery to heat up a can of soup but it seems your options are limited.
 
Per my lease, I am not allowed to have so much as a candle, much less a small butane burner!

I have an old small 900 watt microwave that I would try to use.
Else, I have an electric rice cooker and a crock pot can probably make do with.

I could also raid my two power chairs for a total of 4 lifepo4 24v 100ah batteries. That is a decent emergency power supply that could make last for days if I were conservative and only used the inverter sparingly.
I am also tracking an auction for a WZRELB Split Phase Inverter 3000W Pure Sine Wave 24V. I am not entirely sure, but I suspect that is like having a pair of 1500ah 120Vac inverters that can be bridged into 3 phase 240. That would probably do the trick if there isn't a bidding war over it (now that I let that cat out of the bag!)
 
Per my lease, I am not allowed to have so much as a candle, much less a small butane burner!

Well, in a survival situation, I'd be willing to violate the terms of my lease .

I have an old small 900 watt microwave that I would try to use.

Don't even try it on anything less than a 1500W or higher inverter UNLESS it's an inverter microwave. If you're uncertain if it's an inverter unit, it's not. They damn well let you know. :)

Else, I have an electric rice cooker and a crock pot can probably make do with.

I would expect both of those are on the order of 400W EA. Crock pot would probably not be viable as it runs for hours by definition. If you want to use it to just heat stuff, sure, but a full slow-cooker recipe, probably not.

I could also raid my two power chairs for a total of 4 lifepo4 24v 100ah batteries. That is a decent emergency power supply that could make last for days if I were conservative and only used the inverter sparingly.

Not too bad. 10.2kWh. In a survival situation with minimal power use, 1-2kWh/day feels like you're living in luxury compared to no power at all.

I am also tracking an auction for a WZRELB Split Phase Inverter 3000W Pure Sine Wave 24V. I am not entirely sure, but I suspect that is like having a pair of 1500ah 120Vac inverters that can be bridged into 3 phase 240. That would probably do the trick if there isn't a bidding war over it (now that I let that cat out of the bag!)

Not 3 phase. It's simply two legs of 120V, each with 1500W. I have a WZRELB 24/2000 120V unit. It was my "starter system." I was very pleased with it, and I retained it as a backup should my other layers of backup fail.
 
Well, in a survival situation, I'd be willing to violate the terms of my lease .



Don't even try it on anything less than a 1500W or higher inverter UNLESS it's an inverter microwave. If you're uncertain if it's an inverter unit, it's not. They damn well let you know. :)



I would expect both of those are on the order of 400W EA. Crock pot would probably not be viable as it runs for hours by definition. If you want to use it to just heat stuff, sure, but a full slow-cooker recipe, probably not.



Not too bad. 10.2kWh. In a survival situation with minimal power use, 1-2kWh/day feels like you're living in luxury compared to no power at all.



Not 3 phase. It's simply two legs of 120V, each with 1500W. I have a WZRELB 24/2000 120V unit. It was my "starter system." I was very pleased with it, and I retained it as a backup should my other layers of backup fail.
Can I ask, "what would something like that be worth", should I get serious about the one I am watching?

How about a pig and a goat?
 
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And I have a 3000W, 48Vdc 120Vac WZRELB that I have beat like a rented mule for over a decade and it refuses to die. I even ran a 12,000 pound boat lift with it for a summer. It would overload, but protect itself each time it failed.

That long ago I paid $379 new.

Heh... Being Bezo's bitch, I can look it up... mine cost me $279 5 years ago... :p

Heh... $239 now...

 
I hope my 10ah 29.2 Lifepo4 charger will work with this pair of 50ah in series Renogys. I realize that my DIY builds are prismatics and these are 18650 lifepo4 cells or something. The same charger will work, right?

A few thoughts:

Make sure the Renogy battery BMS is rated for series use. Link a product spec sheet if you’re not sure. EDIT: SEE POST BELOW ASAP!

You will need to check each battery voltage occasionally to be sure they are staying balanced. You don’t need to disconnect the series setup, just properly place your DVM probes across one battery at a time.

At 29.2 V that is 3.65 V per cell. A bit high for my taste. Read some of the millions of posts on proper charge Voltage per cell and draw your own conclusions.
 
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Bad news, but glad we caught it in time (I hope). I found the model number on the picture you posted and then found Renogy’s documentation for the batteries you bought.


To quote from that document :

“DO NOT string batteries in series. Doing so can cause catastrophic failure.”

I understand that “Catastrophic Failure “ is a bad thing. 😎.

I assume that you are already on eBay looking for a 12V inverter to use with the Renogy batteries?

It seems you are good at making lemonade when life gives you lemons so I have no doubt you will sell something or make something else work.
 
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