Hi. I'm Sarath Jaladi, applications engineer here at BRECOflex and today I'm here to
talk about the second part of our SM5 tension meter series. In this video I'll
be talking about how to interpret the value displayed on the screen of your
tension meter and convert that into a pre-tensioned value that can be used in
your other calculations. All the information I'm about to present can be
found here in our SM5 tension meter bulletin on the second page of the
inside. The SM5 tension meter bulletin can also be downloaded just the link below.
To calculate the pretension Fv using frequency F read from the meter, we will use
the first equation listed in the SM5 tension meter bulletin. This equation: Fv
equals F squared times L squared x 4mb. Fv in this equation is the current
pre-tension in Newtons. F is the frequency read from the meter and hertz. L is
the free vibrating span length in meters. M is the belt mass in kilograms per
meter of length per centimeter of belt width. B is the belt width in centimeters. On the
other hand to determine the correct frequency required to achieve a target
pretension we will use the second equation listed in the SM5 tension meter
bulletin. This equation F equals the square root of Fv divided by L squared
times four times M times B. In this equation F is the frequency reading in
Hertz. Fv is the target pretension in Newtons. L is the free vibrating span length in
meters M is the belt mass in kilograms per meter of belt length per centimeter
of belt width, and B is the belt width in centimeters.
Now that we have reviewed the two equations let's go ahead and do some
calculations to demonstrate how these equations work. First let's look at an
example where we use the tension meter to obtain a frequency of 47 Hz from
the 50 millimeter wide AT10 belt with a center-to-center distance is 500
millimeters. We use the first equation listed in the SM5 tension meter bulletin.
using the following values. We will take the frequency of the belt to be 47 Hz,
the length of the belt to be 500 millimeters or .5 meters. We will take the
AT10 belt to have a belt mass of 0.58 kilograms per meter of belt length
per centimeter of belt width, and we will take "b" to be five centimeters. Plugging
in all these values and doing the math yields an answer of
640.61 Newtons Now that we have an answer for the tension in belt
let's look at the other case. Say we want attention of 700 Newton to be applied to
a belt from the previous example. We will refer to the second equation and use the
following values: 700 Newtons for the target pretension, 500 millimeters or
.5 meters for the belt length, an AT10 belt with a belt mass of
0.5 8 kilograms per meter of belt length per centimeter of belt width, and B will
be five centimeters of belt width. Plugging these values and running the
calculations will give us an answer 49.1 three Hz as our target frequency.
For more information about the SM5 tension meter or to download our SM5 tension
meter bulletin, please visit the link below. To order an SM5 tension meter
please call the number at the end of this video. Don't forget to subscribe to
our Youtube channel for more how-to videos and product demos. Thanks for watching.