Speed Conversion

Ft/Min In/Min In/Sec Sec/In Ft/Min ln/Min In/Sec Sec/In
1 12 0.2 5.000 60 720 12 0.0833
2 24 0.4 2.500 70 840 14 0.0714
3 36 0.6 1.667 80 960 16 0.0625
4 48 0.8 1.25 90 1,080 18 0.0556
5 60 1 1 100 1,200 20 0.05
6 72 1.2 0.833 125 1,500 25 0.04
7 84 1.4 0.714 150 1,800 30 0.0333
8 96 1.6 0.625 175 2,100 35 0.0286
9 108 1.8 0.556 200 2,400 40 0.025
10 120 2 0.5 225 2,700 45 0.0222
11 132 2.2 0.455 250 3,000 50 0.02
12 144 2.4 0.417 275 3,300 55 0.0182
•13 156 2.6 0.385 300 3,600 60 0.0167
14 168 2.8 0.357 350 4,200 70 0.0143
15 180 3 0.333 400 4,800 80 0.0125
16 192 3.2 0.313 450 5,400 90 0.0111
17 204 3.4 0.294 500 6,000 100 0.01
18 216 3.6 0.278 600 7,200 120 0.0083
19 228 3.8 0.263 700 8,400 140 0.0071
20 240 4 0.25 800 9,600 160 0.0063
25 300 5 0.2 900 10,800 180 0.0056
30 360 6 0.167 1,000 12,000 200 0.005
35 420 7 0.143 1,500 18,000. 300 0.0033
40 480 8 0.125 2,000 24,000 400 0.0025
45 540 9 0.111 3,000 36,000 600 0.0017
50 600 10 0.1 5,000 60,000 1,000 0.001

Example: Find the time the photocell will see a ¼” registration mark at 70 Ft/Min

Answer: .25 inches X .0714 Sec/In = .018 Seconds or 18 mili-seconds.

For Speeds Not Given: Ft/Min ÷ 5 = In/Sec 1 ÷ In/Sec = Sec/In

1.000 = 1 second

0.100 = 100 mili-second

0.010 = 10 mili-second

0.001 = 1 mili-second

0.0001 = 100 micro-second