55 Amp Converter Charge Times

Simple answer NO. NABS

Charge times are related to "charging rates" which IMO, mean the percentage of the initial (should be constant) charging amps in Stage 1 [Bulk] before amps taper in Stage 2 [Absorption]

Batteries are fairly consistent in this regard so you can do proportional and get good estimates.

My (in)famous ugly graph Tells All. You can derive from that how it would go in your situation (or if you can't, further posts might assist)

otrfun wrote:
It it possible for a 55 amp converter (with a 14.4 volt quick-charge mode) to take a new Interstate SRM-24 series Marine/RV battery that's discharged to 11.90 volts and charge it to 90% (12.58 volts) in 3-4 hours?

I realize discharging below 50% is not recommended, but I'm trying to get a feel for a worst-case scenario.

Thanks!

Yep, that's a good guess, being as there is no meter measurement in existence that measures an accurate % of battery SOC.