It's the voltage that matters here, you need to be above 110/120 volts dc or else the solar inverter limits the current it charges the batteries with anyway.
As i said before if you only feed it 50v dc input it will be limiting it's current output to the battery to a measly 500w or 16 amps at 30 volts. Which means if you're not going to give it the necessary 110/120v dc input to unlock it's current limiting you might well be better off with a 16amp battery charger on the batteries instead of building something and if you try to find a 120v ourput 1500w ac-dc power supply you might find you're cheaper and more efficient just buying a 60 amp 24v battery charger instead.
Can you clarify a few things, such as which model of tristar do you have, 150v or 600v input limit? and what voltage are your solar cells giving out?
The tristar really is a beast of a charge controller, it will take over 4.5kw of dc input to cause any damage to it and that is way over what you can get out of a mains outlet.
One note of caution for you as others may not realise. You must NEVER connect negative DC output of the tristar, the solar negative of the solar array or the battery bank negative to a common ground. You will end up with a fire - This is one thing that NEC standard get's wrong as it states to do the opposite.
According to Morningstar, my CC is max input of 150v. The total input watts on CC's is factored to what voltage your battery bank is...mine is 24v, so max of 1500 watts input. If I was doing a 12v bank, max would be something like 800 watts, and a 48v bank would be much higher...perhaps that's where your 4.5kw number comes from.
I'm not really understanding what you mean by "it's the voltage that matters". I'm guessing that you're looking at it from a perspective of the only amps coming in are straight from the 120v line, which would be 15-20? I think I need a power source that also boosts the amp output...like most chargers, converters, etc.
It's sounding like I should really work on this from the angle of trying to figure out how to use the Meanwell RSP-1500-48 I linked in OP...it puts out 1536 watts. But I've seen build threads where novices get stumped trying to make similar switching units perform to spec...making the magic blue smoke appear isn't something I'm real keen on with a $400 unit ![Wink ;)](https://www.fieldlines.com/Smileys/default/wink.gif)
What I'm saying is that if your 150v max input morningstar tristar doesn't get at least 110v dc input from a solar array then it limits the battery charging to only 500 watts. It needs at least 110v input to get it to charge over 500 watts and 500 watts on a 24 volt battery bank would equalise over 30v so that would only leave you with 16 amps charging your battery. To get between 16 and 60 amps at the battery you need to feed it with 110v DC. (read the manual)
The 4.5kw reference is to the maximum amount of surge that the tristar can withstand on the dc input, meaning it's tough. To put that it into perspective
a 110v ac mains plug can never deliver more than a measly 1760w with a 16 amp fuse/breaker.
You
could use the Meanwell RSP-1500-48 charger, no problem. but since it's only giving 48v input to the tristar you will only get 16 amps at the battery or 500 watts, whichever is greater. Meaning the 1500 watt power ceiling of the Meanwell RSP-1500-48 never gets used, you only ever make use of 1/3 of it's potential and you would be cheaper buying a 16amp ($90) or greater 24v battery charger since the Meanwell RSP-1500-48 is around $200 at the cheapest price i could find it.
To get the full 60 amp output, the consensus is you're going to need a 120v to 120v transformer rated to 15 amps, to keep you safe from bad practice wiring, a bridge rectifier to turn it into dc and a few capacitors to keep the voltage steady. If you put together all of what we have said you should have a solution.
The only thing left to explore is, is it cheaper to buy a 60 amp 24v battery charger to connect straight to the battery bank, or is it cheaper and within your limits to build a 120v dc power source for your tristar to give it a 60 amp output, because i don't think anyone makes them.