yeah always measure TEC power consumption directly, not through a kill-a-watt etc, PSU's can vary from like 50-90% efficiency depending on the percentage of total PSU wattage being used.
12v 12A is perfect.
Correct mounting pressure can result in a change in amperage, either up or down, I've never tested it though but I have heard others report amperage dropping a bit with higher pressure. That might have been too much pressure though.
300PSI is absolute max pressure I think, there is a pretty basic formula you need to use to figure out how much torque per bolt. I think with 4 x M4 bolts that aren't oiled it's about 1.5Nm/bolt for a 62mm TEC. I'll get the formula and check.Edit
, here is the formula from Ultrasonics forum, guide to TEC's. http://www.tecpeltier.com/viewtopic.php?f=21&t=19&sid=585c445502e1f2364a6af9cfa3b75864
You should apply about 300 PSI to your TEC to work out how to apply this pressure see the equation below
T = (C x D x F x in2) / (# of screws)
Using the following equation you can solve for torque per screw:
T = torque per screw (in-lbs)
C = torque coefficient (0.20 as received, 0.15 lubricated)
D = nominal screw size (4/40 = 0.112, 6/32 = 0.138, 8/32 = 0.164)
F = Force (lbs / in2)
in2 = Module surface area (length x width)
This per module
C= 0.20 (who oils their bolts)
D= 0.157 (4mm)
F= 300 (150 is the minimum recommended)
in2= 3.875 (50x50mm TEC)
# of screws = 2
18.25125 = (0.20 x 0.157 x 300 x 3.875) / (2)
So to achieve 300psi on the TEC i'd have to tighten each bolt up to 18.25 inch pounds. i'll probably round that up to 20inch pounds. This is actually a very SMALL amount of pressure and will require a special tool to apply. It's my experiences that a TEC with a higher couple count ( higher voltage ) can not withstand as much force as a lower voltage TEC AND the Pressure applied really isn't as important as widely though.
Lets go with M4 bolts (0.157") and use 4 of them without oil, aiming for 300psi on a 62mm TEC .
(0.20 x 0.157 x 300 x 5.958) / (4) = 14 inch pounds
so 14 inch pounds per bolt. or 1.58Nm per bolt. That's not very much at all really.Edited by LiamG6 - 5/4/17 at 6:44pm