Monthly Archives: March 2012

What is the Moisture Meter?

Posted by on March 26, 2012 No comments

Moisture Meter is used to measure the water content/percentage of water in a given substance e.g. seeds, food products and any others. It estimates the moisture content of certain textile materials by utilizing the relationship which exists between their moisture condition and Electrical Resistivity.

The Moisture Meters depend on the Conductivity Measurements, Capacitance Measurement and Electrical Resistivity. These meters are equipped with Sensors known as Transducers which help in converting onekind of energy into another type of energy. A novel Moisture Meter sensor depends on the following principle.

Frequency measurement; meter operates on the principle of non destructive measurement

Time domain measurement; meter works on the principle of change in the time duration of passage of the pulse through the material.

These Moisture meters provide non-destructive measurement content in soap, soap cake, paper, cement and food industries such as-biscuits, chocolates sugar syrups i.e. no damage to material.

Here are some different types of Moisture Meters which are used for different purposes.

1、Moisture Meter for Wood
The Wood Moisture Meter works on the principle that the wood resistance decreases, as the moisture content in the wood increases. The decrease in the resistance is converted into digital data and the moisture meter displays the percentage of water in the wood. The Moisture Meter consists of two electrodes, which are inserted into the wood, to find out the resistance between them and hence its moisture content.

2、Moisture Meter for Concrete
Concrete Moisture Meters were introduced to check out the moisture content in the concrete slabs that are used in construction. Their principal of working and finding out the moisture content is same as that of the Wood Moisture Meter. The resistance between their electrodes is checked out here too, to find out the moisture content in the concrete. However, they significantly differ in their moisture detection and moisture analysis methods, from the Wood Moisture Meters. They can measure moisture at a depth of 1 inch from the moisture surface. This is required because people working in the field need to know the moisture content at the depths of the concrete slab, to analyze the construction.

3、Moisture Meter for Soil
This moisture analysis is required to find out if the plants in your garden would require watering or not. It may happen that because of rain, the moisture content in the soil is already sufficient and your plants do not need any more water, for a considerable amount of time. Under such cases, a Soil Moisture Meter can be used for the moisture detection and moisture analysis in the soil, to find out regularly, if the plants require any additional watering. If it rains regularly and your plants are getting over watered, then the moisture analysis can help you in determining if you need to take some preventive measures, to cover up your plants from the rain. The Soil Moisture Meter works on the same principle as that of any other ordinary moisture meters.

Application Areas

Food and beverages
Pharmaceuticals
Minerals and chemicals
Plastics and companies
R & D laboratories
Pulp & paper
Textiles
Cosmetics
Paints & coatings
Regulatory Agencies

Mastech MS8264 Digital MultiMeter Review

Posted by on March 22, 2012 1 comment

I’ve been getting back into electronics after a hiatus, while I need a more modern meter that has capacitance and frequency measuring abilities in addition to the usual functions, such as Voltage, Amperage, Resistance, etc. So I searched in the internet and finally found this very inexpensive Mastech MS8264 Digital MultiMeter which are equipped with all the features I needed on www.histest.com. So I ordered this multimeter without any hesitation at once. I have kept this multimeter for several weeks and everything is smooth on its going.

Having been used it for about a month, I think the MS8264 has some Prominent features as  follows:

1、The most remarkable aspect is the audible alert. Sometimes we get in a hurry when we are troubleshooting. We go from one type of measurement to another and sometimes forget that we need to connect the test leads to the other banana jack. The MS8264 addresses that issue by having an audible alert and red blinking led terminals that show you the correct banana jacks that should be used depending on what function you have the meter set on.

2、It has large display and backlight so you can see in dark places. However the backlight only turns on for 5 seconds when light button pressed (it doesn’t continuously stay on).

3、Auto-power off feature helps save battery life. While most meters have this feature, this one beeps when it turns off to alert you of that fact, which is a nice touch.

4、Jack protection feature which prevents you from blowing a fuse or worse if you have the probes connected to the current jacks but you are trying to measure voltage. The meter detects when the probes are inserted all the way into the various jacks and if not correct for the selected function the meter beeps repeatedly and flashes the correct jacks that should be used. The jacks have LEDs around them and the meter also lights up a jack if a probe is not pushed in fully to make proper contact. This is a good safety feature, after all you would not want to test potentially hazardous voltage with a probe not connected properly and get a false “dead, safe to touch” reading only to find out otherwise! That would be a shocking experience!

5、The last one, to the nitty gritty of what a digital multimeter is supposed to do… accurately measure current, resistance, voltage, etc.

Measurement of AC Voltage from AC Mains at my home: 125.5VAC

Measurement of an exact 13.8VDC regulated source: 13.91VDC

Measurement of a 200 Ohm 1% Resistor: 199.2 Ohms

The measurement is accurate and the measuring result can be hold.

In conclusion, I give the MS8264 a thumbs up and all of it’s features and at a reasonable price.

How to Record Lighting Measurements in LUX

Posted by on March 18, 2012 1 comment

Like most natural phenomenon, light can be measured in various units. One unit, called lux, is a measurement of the amount of light a light source gives off based on the space it illuminates in square meters. While a seemingly convoluted measurement, many lighting data sheets give illumination values in lux and the measurement is often used in the field when the absolute amount of light produced, rather than the relative amount, must be obtained. This is especially useful in scientific processes, where this measurement is most often used. Here we will discuss how to record the measurements using a light lux meter.

Instructions：

1.Turn on your light meter.

2.Test your light meter with a calibrated light source, if possible. A calibrated light source is a light source of known brightnesses that can be used to test the accuracy of your light meter. While modern digital light meters rarely drift in their readings, as older analog models were prone to do, it is still advisable to check one’s equipment before proceeding.

3.Set your light meter to measure the amount of light in lux. This is done differently on each light meter and not all light meters can measure light in lux, so make sure your meter is capable of doing this. For specific instructions, consult your meter’s instruction manual.

4.Turn the knob on the lux meter to 2,000. This is the maximum lux value the meter will measure and the lighting of most places will fall below 2,000 lux. If you are measuring an extremely bright source, such as a computer scanner, turn the knob to 20,000 lux. Especially dim sources, like candlelight, can be measured with the lux meter set to 200.

5.Take four to five lux measurements of the space or light source that you are measuring. When doing this, hold the meter at waist level and point it towards and area of even illumination. If your values differ widely, take more measurements and use either the mean (average) or mode — most frequent reading given — as your general lux reading.

6.Use the set of readings, their average or their mode to determine if the space you are measuring is over-lit or under-lit, according to your requirements.

Use a Moisture Meter to Measure the Moisture Content of Wood

Posted by on March 15, 2012 1 comment

Moisture content, as the term suggests, refers to the natural qualities of moisture retention in wood. Lumber manufacturers develop methods of measuring moisture content in order to produce lumber with moisture contents that are suitable to the ultimate use of the wood. Therefore, wood intended for outside decking might require different moisture content measurements than that used for furniture. While, we can use a moisture meter to measure moisture content of wood accurately. This artical will show you how to use a Moisture Meter the Moisture Content of Wood.

1、Determine the reason for measuring moisture content. Wood is a natural, porous material that readily absorbs moisture, but it also has amazing capacities for drying. Wood that has sat in the rain for days can be sufficiently re-dried to usable standards. These standards vary by project, though, so you need to know why the moisture level is important. Additionally, moisture content should be measured in a comparable scenario to the end use of the material.

2、Obtain an electric moisture meter that suits the measurements you need to take. If you know that you’ll be working with a variety of species and types of wood, you’ll need an advanced piece of equipment that is already calibrated with the necessary adjustments for temperature and wood density.Otherwise, you’ll find yourself doing endless calculations trying to get an accurate read on moisture content.

3、Use the electric moisture meter according to the owner’s manual aiming at getting the most accurate reading. There are two types—Probe and Pinless—and each serves a different purpose. Probe are easy to use and very fast, while pinless are more advanced and leave no mark on the wood itself. Prober are more accurate at different depths, while pinless is better for thinner materials where wood damage is not acceptable.

4、Understand the readings. Your lumber provider can tell you what moisture percentage is suitable for a variety of uses. For instance, subflooring should have a moisture content of less than 12 percent in order to be suitable for work. Any higher, and drying steps will need to be taken to prevent unnecessary damage or problems later on. Know what you are doing with the wood and communicate with your provider to determine whether or not your moisture reading is acceptable for the particular job and treatment you intend to do.

Testing Your Circuit Breaker Properly With a Digital Multimeter

Posted by on March 12, 2012 No comments

A digital multimeter can play a great role in testing the performance of your circuit breaker. The digital multimeter is a handy device that facilitates you to check the coltage in electrical circuits. Futhermore, it also helps you determine whether the tested circuit is using AC (alternate current) or DC (direct current). This certain tool will be very helpful when you check whether the circuit breakers in your system work in proper performance or not. Here are some simple steps that you can follow in using an digital multimeter to detect your breaker.

First of all, you are required to open your circuit box. You might find some breakers here, so you have to determine which one that you are going to check first. Usually, each of those breakers powers your house in different portion. You can easily notice which breaker that handle which power by taking a look at the label. If you can not find this information, you should label your breakers right away.

Secondly, you have to turn off all the appliances and lights that are being powered by the certain breaker that you want to check. It is very important to prevent any serious problems such as damaged appliances and lights or even fire.

Thirdly, you need to think about your safety. Put a pair of rubber-soled shoes on and make sure that the area near your circuit box is completely dry. In addition, you should also be very careful off puddles that you might find on the ground. Mop them right away and make sure that the floor or ground is really in dry condition. You really need to check the surrounding environment before testing your breaker in order to avoid the risk of electrical shock.

Fourthly, you should unscrew the metal frame around your breakers. Simply use your screwdriver to unscrew it and you can set it aside. Behind the metal frame, you will find wiring that run through the breakers and also the breakers themselves.

Fifthly,you can set your multimeter to Volts AC. Mostly, wiring systems in home use alternating current, so the Volts AC setting let the multimeter to read the current correctly. DC is usually used in testing the voltage of battery-powered electronics.

Finally, you have to touch one prong of the multimeter to the terminal screw of the breaker. Then, you can touch another prong on the breaker to the ground screw. Your multimeter will give you the readout on how much electricity that flows through your breaker. The ideal readout will be either 120 or 240 volts. If your meter does not read anything, you need to immediately replace your breakers well.

How to Use A Digital Multimeter To Test A Resistor

Posted by on March 8, 2012 No comments

Digital Multimeters have many functions that are useful. One of the things Digital multimeters are very capable of performing is testing components. This article will show you how to use your digital multimeter to test a resistor.

Resistors are typically 2 terminal components whose main purpose is to limit current to other components. A voltage drop occurs between the two terminals and resistance can be calculated using Ohm’ s Law R=V/I; where R = resistance, V = voltage, and I = current.

1.Connect the probes to the digital multimeter.

Connect the black probe to the com (common) port and the red probe to the port marked with the Ohm symbol which looks like an upside down horseshoe. For those of you who remember Greek, the Ohm symbol is the Greek letter Omega.

This digital multimeter has banana jacks for the port plugs. Other digital multimeters may have screw in terminals or BNC plugs.


2.Alligator clips to make work easier

Use alligator clips to attach to the digital multimeter probes. The alligator clips will allow you to work more hands-free and provide a better connection to the component. Use a red and black alligator clip to match the probes.

This process will help you finish the test more easily and obtain more accurate numbers.

3.Connect the alligator clips to each terminal of the resistor.

Most common resistors are the 4 color band type. The first two colors indicate values, the 3rd band indicates a multiplier, and the 4th band indicates % tolerance of the resistor value.

The pictured resistor is red (2), violet (7), orange (x 1000), and gold (5%). This resistor should then theoretically have a value of 2700 Ohms with 5% tolerance of the value. The lower the tolerance value, the better the resistor. 5% tolerance is about as good as a standard resistor as you can buy at stores like Radio Shack.

4.Turn the digital multimeter dial setting to Ohms (Omega).

Some less expensive digital multimeters have Ohm settings with multipliers (x 100, x 1000, etc). The digital multimeter shown is auto ranging so the multiplier will be shown in the screen with the reading.

After completed, let us do the next procedure.

5.Take the digital multimeter reading.

Take the digital multimeter reading. The pictured test shows a value of 27.02 k Ohms. The resistor value is therefore 2702 Ohms. This value is well within the 5% tolerance variance from 2700 Ohms. The resistor is ready for your project.

Now we have got this readings and you can be prepared to do your plan and your project will be sucessful at once.

6.Touch probes on each terminal of the resistor

To test an in-circuit resistor with a digital multimeter, use steps 1 and 4 above. Make sure there is no voltage active in the circuit board. You will probably have to use the probe tips unless you have really small alligator clips. Touch each probe to a terminal of the resistor. For resistor testing you can touch either terminal with the black or red probes.

7.Take the digital multimeter reading.

Take the digital multimeter reading. This resistor has the color code green, brown, brown, gold, and should therefore have the value of 510 Ohms. The digital multimeter reads 509 Ohms. The digital multimeter test shows a good resistor.

HisTest.com Promotional Coupon Code March 2012

Posted by on March 5, 2012 No comments

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How to Test a Battery Using a Digital Multimeter

Posted by on March 4, 2012 No comments

Batteries provide the needed power to use many of the portable devices that we own.Sometimes, you need to know how much juice is left in the cell before it runs out. You can use a digital multimeter to test the voltage of any battery. If you have batteries around the house or office and are unsure if they will provide adequate power, a digital multimeter will help. Testing your batteries can be done in minutes. Common household batteries range from 1.5 to 9 volts.

1. Set up your digital multimeter. Place the black probe plug into the COM port and the red probe plug into the V port (usually red). The probes can either be needle type or have alligator clips.

2. Turn on your digital multimeter. If your meter has a dial, turn it from the “Off” position to “DC” voltage position. The DC voltage position has the V with the straight and dashed line over the top.

3. Place the black probe lead on the negative (-) side of the battery. Then place the red probe lead on the positive (+) side of the battery. On a typical alkaline battery — such as size AA, AAA, C or D — the plus side has the bump and the negative side is flat. For a 9-volt battery, the positive and negative connections are both on top; the positive side is the smaller, more round connection.

4. Read the voltage on your digital multimeter. This is the DC voltage output coming from the battery. AA, AAA, C and D batteries will each produce 1.5 volts. New alkaline batteries will read slightly higher values. Any voltage over 1.5 volts or 9 volts is good. Rechargeable batteries are many times rated lower than 1.5 volts for size AA, AAA, C and D. They often range from 1.25 to 1.4 volts. Read the jacket on the battery to see what the battery voltage is rated. Your digital multimeter will help you to read the battery voltages to test the batteries so you know what is good.