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4-20ma is a standard range used in process controls to indicate measured values. For instance, a pressure instrument may output 4ma to indicate 0 psi, up to 20 ma to indicate 100 psi, or full scale. Or, to control a variable-speed motor drive, 4 ma may mean to stop the motor, and 20 ma to run at full speed. The reason that 4ma is chosen instead of zero is for fail safe operation. A broken wire always results in 0 ma. Suppose our signal right now is 12 ma, and this causes a ventilation fan to run at 50% speed. Suddenly the signal drops to 0 ma. Now, if our range was 0-20 ma, does this change mean stop the fan? Or does it mean the signal wire just broke? There would be no way to tell. With a 4 ma low range, we would know that 0 ma was a broken wire. Then instead of stopping the fan, we could set it to some default speed, or simply continue at the previous speed until the wire was repaired.
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What is the range of standard deviation of 18 15 12 13 17 14 19 20 8?
The range is 12 and the standard deviation is 3.822448314.
In the movie Next Friday and Friday after next was chico a standard bull terrier or a miniature?
miniature bull terrier Miniatures range from 20 to 35 pounds, and Chico was larger than that, therefore he would be a standard.
What are the standard sizes for basement windows?
Standard sizes for basement windows typically range from 24 inches by 20 inches to 36 inches by 24 inches.
Are there more than 20 amino acids in existence?
Yes, there are more than 20 amino acids in existence. While there are 20 standard amino acids that are commonly found in proteins, there are also non-standard amino acids that occur naturally or can be synthesized.
How many dogs do the mushers have to have in the race?
13. Typical teams range from 4-20 dogs but i believe the standard is 9.
Is a bacteriophage is larger than a bacterium?
No, a bacteriophage is generally much smaller than a bacterium. Bacteriophages, which are viruses that infect bacteria, typically range from about 20 to 200 nanometers in size, while bacteria usually range from about 0.5 to 5 micrometers. This size difference means that bacteriophages cannot be seen with a standard light microscope, while bacteria can be observed.
What is the standard form of 20?
The standard form of 20 is 2.0 × 101
What is the probability that the sum of the two dice is greater than or equal to 20?
With standard dice, zero.
How large a sample would be needed to have a standard error less than 2 points for population with a standard deviation of 20?
A sample of size 100.
What is the Value of jc Higgins model 20?
The JC Higgins Model 20 was a slide-action shotgun made for Sears by High Standard. Value, depending on condition, can range from $100-$225.
What is a 6mm erythrocyte sedimentation rate?
It's normal. The standard range is 0-20 mm/hr.
What is the greatest range in cordless phones?
The range of cordless phones typically range up to 5 miles at best. However, you will rarely need more than 20 feet of cordless range if you are in your house.
