To compute the power in watts on the mosi2 heating element the length of the hot zone, the surface area of the hot zone, and the watt loading in watts per cm2 must be determined.
The heating length of a “U” shaped element consists of 2 legs and a 180º bend. Use the formula below to calculate the overall heating length.
Step 1
To obtain the total length of the hot zone in mm, use the equation: Total Hot Zone (LH) = 2(Le) plus (z) the amount from the following table, column 3.
LH=2(Le)+z
Step 2
| 1 | 2 | 3 | 4 |
| Hot Zone Diameter mm |
On- Center mm a |
Length to be added to Le mm z |
Surface Area (mm2) for 1 mm of length c |
| 3 | 20 | 8.40 | 9.42 |
| 3 | 25 | 11.25 | 9.42 |
| 4 | 20 | 7.40 | 12.56 |
| 4 | 25 | 10.25 | 12.56 |
| 6 | 40 | 16.80 | 18.84 |
| 6 | 50 | 22.50 | 18.84 |
| 6 | 60 | 28.20 | 18.84 |
| 9 | 50 | 19.50 | 28.26 |
| 9 | 60 | 25.20 | 28.26 |
| 12 | 60 | 22.20 | 37.68 |
To obtain the surface area (SA) of this hot zone in square cm, select from Table C, column 4, the surface area (c) of 1 mm length for the element diameter 3, 4, 6,9, 12, or 24 mm. Multiply this by the total from step 1 (LH).
This number will be the total surface area of the hot zone in square mm. To convert the units from square mm to square centimeters (cm), divide by 100.
