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So a LP120 has the same quantity of gas as an HP120 but the HP120 requires 3442psi to get it because the tank has a lower volume(smaller than an LP120)?
What about wattage, led or halogen etc.. for can lights?
Mainly, HP vs LP tanks and what type of canister tanks are available, what are each's strong and weak points. What are decent brands of can lights.
"May I take the opportunity to add to the schooling process?"...
I am not fond of HP cylinders; they are heavier than LP’s and a low percentage of filling stations are capable of filling them to their potential. A lot of divers prefer the HPs because of potential higher volumes; I would just get a larger cylinder for recreational diving or go twins if plan on tech stuff.
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......a low percentage of filling stations are capable of filling them to their potential. .......
"May I take the opportunity to add to the schooling process?"
A PST E7-80 (3442 psi) weighs 28 lbs. empty
A PST LP-80 (2400 psi) weighs 34 lbs. empty
A standard aluminum 80 (3000 psi) weighs about 31 lbs. empty
I haven't been in a math class in a very long time but I'm fairly certain 28 is less then 31 or 34. So for equivalent sized cylinder the high pressure cylinder is lighter.
... a low percentage of filling stations are capable of filling them to their potential.
I don't buy this. Most commercial compressors are more than capable of pumping 3500psi needed to fill a HP cylinder. The fill operator may not take the time time to properly fill the HP cylinder to the specified pressure (too lazy, ignorant, etc..), but this is an operator issue, not an equipment issue in most cases.