Resistance Decade Box anyone using one

Tim McElwain

They are for measuring in place of the sensors used on a lot of the control modules for boilers. They will check whether the control module is correctly sensing temperature. You connect the decade box temporarily in place of the sensor and read the corresponding temperature on the dispaly screen of your module system.



What is a Resistance Decade Box?

 <span style="color:#000000">Resistance decade boxes</span>

A resistance decade box or resistor substitution box is a unit containing resistors of many values, with one or more mechanical switches which allow any one of various discrete resistances offered by the box to be dialed in. Usually the resistance is accurate to high precision, ranging from laboratory/calibration grade accuracy of 20 parts per million, to field grade at 1%. Inexpensive boxes with lesser accuracy are also available. All types offer a convenient way of selecting and quickly changing a resistance in laboratory, experimental and development work without needing to attach resistors one by one, or even stock each value. The range of resistance provided, the maximum resolution, and the accuracy characterize the box. For example, one box offers resistances from 0 to 24 megohms, maximum resolution 0.1 ohm, accuracy 0.1%





<strong>Available at</strong>

<strong>IET Labs Inc. for Resistance Decade Box. The phone number is 800-899-8438 or e-mail </strong><strong>sales@ietlabs.com</strong><strong> .</strong>



<strong>RESISTANCE DECADE BOX SELECTION GUIDE</strong>

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<strong>IET Labs manufactures a full line of resistance decade boxes that will meet any need.  Whatever your application, IET Labs has a decade box solution. Our resistance decade boxes can be custom built to your specifications, so you do not have to pay for what you don't need. </strong>

<strong>Please contact our sales department for your next resistance decade box requirement.</strong>



<span><strong>Low Cost Field Grade Resistance Decade Box </strong></span>





<strong>Series</strong>

<strong>Type</strong>

<strong>Basic Accuracy</strong>

<strong>Range</strong>

<strong>Max.

Resolution</strong>

<a href="http://www.ietlabs.com/IET/RSbox.html">[b]RS[/b]</a>

<strong>General / Field grade</strong>

<strong>0.1% (or better) to 1%</strong>

<strong>.001Ω -100 MΩ</strong>

<strong>10 mΩ</strong>

<a href="http://www.ietlabs.com/IET/RCSbox.html">[b]RCS[/b]</a>

<strong>Field grade Resistance and Capacitance Box</strong>

<strong>0.1% (or better) to 1%</strong>

<strong>.001Ω -100 MΩ</strong>

<strong>10 mΩ</strong><em>Low Cost Microprocessor Controlled Resistance Decade Box </em>



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<strong>Series</strong>

<strong>Type</strong>

<strong>Basic Accuracy</strong>

<strong>Range</strong>

<strong>Max.

Resolution</strong>

<a href="http://www.ietlabs.com/IET/ohmSource.html">[b]OS-250[/b]</a>

<strong>Basic Model</strong>

<strong>0.1% </strong>

<strong>0-24 MΩ</strong>

<strong>1 Ω</strong>

<a href="http://www.ietlabs.com/IET/ohmSource.html">[b]OS-260[/b]</a>

<strong>Wide Range</strong>

<strong>0.1%</strong>

<strong>0-24 MΩ</strong>

<strong>0.1 Ω</strong>

<a href="http://www.ietlabs.com/IET/ohmSource.html">[b]OS-270[/b]</a>

<strong>High Accuracy </strong>

<strong>0.01%</strong>

<strong>0-1.5 MΩ</strong>

<strong>0.01 Ω</strong>

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Jason_13

What????

I have just been using a rheostat, meter a setting from the chart, hook it to either a sensor molex connector or terminal strip. As long as it is within a degree or two I am happy.

Tim McElwain

Not a problem Jason

the RDB is just another way of proving whether the sensor is the problem or the control board. Several companies mention it in there troubleshooting procedures. One in particular is Weil-McLain for their Ultra 3.