<![CDATA[Minnesota Measurement Instruments LLC: Latest News]]> https://www.meter-depot.com Sun, 19 Apr 2026 11:28:11 +0000 <![CDATA[Coupon codes canceled, price increases necessary]]> https://www.meter-depot.com/blog/coupon-codes-canceled-price-increases-necessary/ Thu, 21 Nov 2024 13:23:05 +0000 https://www.meter-depot.com/blog/coupon-codes-canceled-price-increases-necessary/ On November 15 we had to discontinue all rebate coupons. Reason for this is that in the last few months the shipping costs for incoming goods significantly increased. We also see increased prices at the factories that make our raw components.
In addition we see a spike in orders. If there is a new 60% or 100% tariff on goods from China in 2025, which originates a lot of the thermocouple raw materials, this will lead to significantly higher prices for all our thermocouples and connectors. In anticipation of that many of our OEM customers have started to order large quantities to lock in current prices. This leads to longer lead times for all our products. We still try to prioritize next day and second day orders, some other orders may see a 1-2 day additional processing time.

]]> On November 15 we had to discontinue all rebate coupons. Reason for this is that in the last few months the shipping costs for incoming goods significantly increased. We also see increased prices at the factories that make our raw components.
In addition we see a spike in orders. If there is a new 60% or 100% tariff on goods from China in 2025, which originates a lot of the thermocouple raw materials, this will lead to significantly higher prices for all our thermocouples and connectors. In anticipation of that many of our OEM customers have started to order large quantities to lock in current prices. This leads to longer lead times for all our products. We still try to prioritize next day and second day orders, some other orders may see a 1-2 day additional processing time.

]]> <![CDATA[Thermocouple tip contamination with other metals has no effect]]> https://www.meter-depot.com/blog/thermocouple-tip-contamination-with-other-metals-has-no-effect/ Wed, 31 Jan 2024 11:54:04 +0000 https://www.meter-depot.com/blog/thermocouple-tip-contamination-with-other-metals-has-no-effect/ There is the claim that contaminating the tip of a thermocouple with other metals will lead to a wrong reading. It is for example claimed that solder touching the tip will not allow you to read an accurate solder iron temperature. 

This is not the case, other metals at the thermocouple tip do not impact the measurement. The reason for this is that the Seebeck effect is an electrical potential that is occurring along a temperature gradient in a wire. That means between a hot end and a cold end of a wire. You need two different material with different gradients to be able to measure this gradient in form of a very small voltage signal. The metal at the tip does not impact this, because it is all at the same temperature, there is no temperature gradient and therefore no error.
The only purpose of the weld at the tip of a thermocouple is to make a durable electrical connection between the two wires. The connection can also be made by simply twisting the wires. In other cases the two wires are welded to a metal object, which then makes the electrical connection.

I will demonstrate this with a little experiment.

First I took a 2 ft thermocouple with Teflon PFA insulation, a Fluke calibration block set to 250 C and a NIST traceable K-type thermometer.

In the first step took the simple thermocouple, inserted it in the calibration block, gave it about 5 min to stabilize and read the temperature. I am showing the thermocouple tip and the measurement results. The reading of 251.1 degrees is right within the "special limits of error" or the "select grade" for Type K thermocouples, which is +/-1.1 degree C (standard error is +/- 2.2 C).

In a second step I wrapped the tip with copper wire and repeated the measurement

In step 3 I covered the tip with some leaded solder and repeated the measurement

As you can see, I got Identical readings in all 3 measurements, the differences in the decimal point are negligible fluctuations in the temperature and the reading. 

]]> There is the claim that contaminating the tip of a thermocouple with other metals will lead to a wrong reading. It is for example claimed that solder touching the tip will not allow you to read an accurate solder iron temperature. 

This is not the case, other metals at the thermocouple tip do not impact the measurement. The reason for this is that the Seebeck effect is an electrical potential that is occurring along a temperature gradient in a wire. That means between a hot end and a cold end of a wire. You need two different material with different gradients to be able to measure this gradient in form of a very small voltage signal. The metal at the tip does not impact this, because it is all at the same temperature, there is no temperature gradient and therefore no error.
The only purpose of the weld at the tip of a thermocouple is to make a durable electrical connection between the two wires. The connection can also be made by simply twisting the wires. In other cases the two wires are welded to a metal object, which then makes the electrical connection.

I will demonstrate this with a little experiment.

First I took a 2 ft thermocouple with Teflon PFA insulation, a Fluke calibration block set to 250 C and a NIST traceable K-type thermometer.

In the first step took the simple thermocouple, inserted it in the calibration block, gave it about 5 min to stabilize and read the temperature. I am showing the thermocouple tip and the measurement results. The reading of 251.1 degrees is right within the "special limits of error" or the "select grade" for Type K thermocouples, which is +/-1.1 degree C (standard error is +/- 2.2 C).

In a second step I wrapped the tip with copper wire and repeated the measurement

In step 3 I covered the tip with some leaded solder and repeated the measurement

As you can see, I got Identical readings in all 3 measurements, the differences in the decimal point are negligible fluctuations in the temperature and the reading. 

]]> <![CDATA[Thermocouple to measure the temperature of solder iron tips]]> https://www.meter-depot.com/blog/thermocouple-to-measure-the-temperature-of-solder-iron-tips/ Mon, 29 Jan 2024 15:30:33 +0000 https://www.meter-depot.com/blog/thermocouple-to-measure-the-temperature-of-solder-iron-tips/ When soldering electronics the temperature of the solder iron tip is very important. It is also not easy to measure with a K-type thermocouple, since the K-type wires do not wet out with liquid solder, but rejects it and does not make a good contact with the liquid metal. The standard to measure the tips of solder irons is the Hakko FG-100B tester. But it has s pretty large thermal mass and 3 wires that lead off the heat from the tip. In my eyes not ideal.

For a long time I wanted to make a simple wire thermocouple that could be used with solder irons and that would work with common multimeters that have a thermocouple setting.


The idea was to overcome the solder rejection of the thermocouple wire by wrapping it with a little copper wire.  Many people believe that a 3rd metal at the thermocouple tip would introduce an error, but that is not true. The electrical connection between the two thermocouple leads can be made by any metal, in stainless steel probes this connection is actually the stainless steel cover. 


So when I received a call from a customer this morning, I finally set this into practice. I used a very thin AWG 30 thermocouple with PFA insulation and wrapped the tip 10 times with thin AWG35 copper wire. This thin thermocouple will limit the additional thermal mass and the heat loss through the wire.

I set the solder iron to 330 C and applied a bit of fresh rosin core solder, it did wet out the copper perfectly

I then plugged the thermocouple into the thermometer and held the probe to the tip, it read about 327 deg Celsius

I then took the probe with the copper and the solder at the tip and inserted it into my precision calibration block, which was set to 250.0 degree C.  Even with the additional metals at the tip, the meter read 251.7 C, which is inside the thermocouple specification of +/- 2.2 C. This proves that the readings at the solder iron tip will be accurate with this method.

I will probably launch this as a product shortly, including the adapter that will enable the probe with many multimeters.

]]> When soldering electronics the temperature of the solder iron tip is very important. It is also not easy to measure with a K-type thermocouple, since the K-type wires do not wet out with liquid solder, but rejects it and does not make a good contact with the liquid metal. The standard to measure the tips of solder irons is the Hakko FG-100B tester. But it has s pretty large thermal mass and 3 wires that lead off the heat from the tip. In my eyes not ideal.

For a long time I wanted to make a simple wire thermocouple that could be used with solder irons and that would work with common multimeters that have a thermocouple setting.


The idea was to overcome the solder rejection of the thermocouple wire by wrapping it with a little copper wire.  Many people believe that a 3rd metal at the thermocouple tip would introduce an error, but that is not true. The electrical connection between the two thermocouple leads can be made by any metal, in stainless steel probes this connection is actually the stainless steel cover. 


So when I received a call from a customer this morning, I finally set this into practice. I used a very thin AWG 30 thermocouple with PFA insulation and wrapped the tip 10 times with thin AWG35 copper wire. This thin thermocouple will limit the additional thermal mass and the heat loss through the wire.

I set the solder iron to 330 C and applied a bit of fresh rosin core solder, it did wet out the copper perfectly

I then plugged the thermocouple into the thermometer and held the probe to the tip, it read about 327 deg Celsius

I then took the probe with the copper and the solder at the tip and inserted it into my precision calibration block, which was set to 250.0 degree C.  Even with the additional metals at the tip, the meter read 251.7 C, which is inside the thermocouple specification of +/- 2.2 C. This proves that the readings at the solder iron tip will be accurate with this method.

I will probably launch this as a product shortly, including the adapter that will enable the probe with many multimeters.

]]> <![CDATA[Transferring some of our products to a partner company]]> https://www.meter-depot.com/blog/transferring-some-of-our-products-to-a-partner-company/ Thu, 09 Feb 2023 12:24:18 +0000 https://www.meter-depot.com/blog/transferring-some-of-our-products-to-a-partner-company/ A few months ago we decided to transfer a range of our J-type products to a new partner, Northern Lights Manufacturing. The will specialize on Type J products and give a much wider product range. Check them out here:

https://www.northernlightsmanufacturing.com/]]> A few months ago we decided to transfer a range of our J-type products to a new partner, Northern Lights Manufacturing. The will specialize on Type J products and give a much wider product range. Check them out here:

https://www.northernlightsmanufacturing.com/]]> <![CDATA[T-type thermocouples for satellite research and manufacturing]]> https://www.meter-depot.com/blog/ttype-thermocouples-for-satellite-research-and-manufacturing/ Sat, 30 Jul 2022 08:32:56 +0000 https://www.meter-depot.com/blog/ttype-thermocouples-for-satellite-research-and-manufacturing/ Satellites operate in the vacuum and cold of space, therefore they have to undergo extensive testing here on earth. A few months ago we received a large order for a range of Teflon PFA insulated T-type thermocouples from researchers and manufacturing engineers working on satellites for a large constellation. T-type thermocouples are especially suitable for measuring cold temperatures and are frequently used in cryogenics. And the PFA plastic insulation is very stable at cold temperatures, though brittleness still increases when it is put in liquid nitrogen. 
T-type thermocouple wire is available in a range of gauges, AWG 36 (0.125 mm), AWG 30 (0.25 mm) and AWG 24 (0.5 mm) and thermocouples from these wires can be made to any length you need. Contact me to discuss your needs.   We also supply T-type extension cables and can make cable assemblies to your specification.

https://www.meter-depot.com/t-type-thermocouples/?sort=featured&page=1

]]> Satellites operate in the vacuum and cold of space, therefore they have to undergo extensive testing here on earth. A few months ago we received a large order for a range of Teflon PFA insulated T-type thermocouples from researchers and manufacturing engineers working on satellites for a large constellation. T-type thermocouples are especially suitable for measuring cold temperatures and are frequently used in cryogenics. And the PFA plastic insulation is very stable at cold temperatures, though brittleness still increases when it is put in liquid nitrogen. 
T-type thermocouple wire is available in a range of gauges, AWG 36 (0.125 mm), AWG 30 (0.25 mm) and AWG 24 (0.5 mm) and thermocouples from these wires can be made to any length you need. Contact me to discuss your needs.   We also supply T-type extension cables and can make cable assemblies to your specification.

https://www.meter-depot.com/t-type-thermocouples/?sort=featured&page=1

]]> <![CDATA[T-type thermocouples for bumblebee research]]> https://www.meter-depot.com/blog/ttype-thermocouples-for-bumblebee-research/ Sat, 30 Jul 2022 08:02:24 +0000 https://www.meter-depot.com/blog/ttype-thermocouples-for-bumblebee-research/ Recently I was contacted by a professor at a Wisconsin University. He is researching bumblebees and wanted to measure and record the temperature inside their nests. Due to the need for more accurate measurements we settled on T-type thermocouples and to minimize the impact from the insulation we used a teflon PFA insulated wire, which is very inert and will lot leach any chemicals. We made these thermocouples in a range of lengths, up to 5 meter (15 ft) long.  Do you have a special measurement task? I am happy to help!

https://www.meter-depot.com/long-t-type-thermocouple-awg24-with-teflon-pfa-insulation-5m-with-bare-end/

]]> Recently I was contacted by a professor at a Wisconsin University. He is researching bumblebees and wanted to measure and record the temperature inside their nests. Due to the need for more accurate measurements we settled on T-type thermocouples and to minimize the impact from the insulation we used a teflon PFA insulated wire, which is very inert and will lot leach any chemicals. We made these thermocouples in a range of lengths, up to 5 meter (15 ft) long.  Do you have a special measurement task? I am happy to help!

https://www.meter-depot.com/long-t-type-thermocouple-awg24-with-teflon-pfa-insulation-5m-with-bare-end/

]]> <![CDATA[Price changes are coming]]> https://www.meter-depot.com/blog/price-changes-are-coming/ Tue, 08 Mar 2022 12:45:13 +0000 https://www.meter-depot.com/blog/price-changes-are-coming/ Over the last year the price of nickel, a main input for K-type thermocouples, has increased tremendously. The price had slowly increased by about 75%, and over the last few weeks then jumped to and 160% increase year over year. Add to that the increased cost of shipping, which tripled over the last year and probably will go up even more with the rising gas prices. This means that the prices for all thermocouples will increase over the coming weeks. The impact will vary, depending on how much nickel is in the individual wire or connector, and what the total weight is.

]]> Over the last year the price of nickel, a main input for K-type thermocouples, has increased tremendously. The price had slowly increased by about 75%, and over the last few weeks then jumped to and 160% increase year over year. Add to that the increased cost of shipping, which tripled over the last year and probably will go up even more with the rising gas prices. This means that the prices for all thermocouples will increase over the coming weeks. The impact will vary, depending on how much nickel is in the individual wire or connector, and what the total weight is.

]]> <![CDATA[Ultra thin K-type and T-type thermocouples]]> https://www.meter-depot.com/blog/ultra-thin-ktype-and-ttype-thermocouples/ Mon, 04 Mar 2019 19:52:07 +0000 https://www.meter-depot.com/blog/ultra-thin-ktype-and-ttype-thermocouples/ I get more and more requests for ultra thin thermocouples, both in K-type and T-type versions. Customers need them in low heat loss or fast reacting temperature measurements. In the past our thinnest wire was AWG30 (0.255 mm, or about 10 mils). We now carry some AWG36 wire (0.127 mm or about 5 mils) with an especially thin dual insulation.
Very soon we will offer pre-made and custom thermocouples in this new thin gauge wire.

In the picture you see the AWG30 wire with single insulation compared to the new AWG36 wire with double FEP insulation, the inside color coded according to ANSI, yellow for + and red for -, the outside brown.

]]> I get more and more requests for ultra thin thermocouples, both in K-type and T-type versions. Customers need them in low heat loss or fast reacting temperature measurements. In the past our thinnest wire was AWG30 (0.255 mm, or about 10 mils). We now carry some AWG36 wire (0.127 mm or about 5 mils) with an especially thin dual insulation.
Very soon we will offer pre-made and custom thermocouples in this new thin gauge wire.

In the picture you see the AWG30 wire with single insulation compared to the new AWG36 wire with double FEP insulation, the inside color coded according to ANSI, yellow for + and red for -, the outside brown.

]]> <![CDATA[Updating Our Website]]> https://www.meter-depot.com/blog/updating-our-website/ Fri, 29 Jun 2018 11:38:13 +0000 https://www.meter-depot.com/blog/updating-our-website/ We are updating the website and now will offer real time shipping calculations, this will allow us to reduce the price on many items, and especially small items like thermocouple connectors will get cheaper.

During the transition the can be hiccups. So if something in the checkout or the shipping cost does not seem right, please contact me.

We are also adding many new items. If you see one of our thermocouples on Amazon or ebay, but not on this website, please notify me and we will add them immediately.

We also offer custom thermocouples. If you need a special length or a new feature, write us and we will try to make a thermocouple to your specification.

]]> We are updating the website and now will offer real time shipping calculations, this will allow us to reduce the price on many items, and especially small items like thermocouple connectors will get cheaper.

During the transition the can be hiccups. So if something in the checkout or the shipping cost does not seem right, please contact me.

We are also adding many new items. If you see one of our thermocouples on Amazon or ebay, but not on this website, please notify me and we will add them immediately.

We also offer custom thermocouples. If you need a special length or a new feature, write us and we will try to make a thermocouple to your specification.

]]> <![CDATA[How to wire the high temperature K-type thermocouple for kiln, furnace and forge]]> https://www.meter-depot.com/blog/how-to-wire-the-high-temperature-ktype-thermocouple-for-kiln-furnace-and-forge/ Sat, 30 Dec 2017 20:09:27 +0000 https://www.meter-depot.com/blog/how-to-wire-the-high-temperature-ktype-thermocouple-for-kiln-furnace-and-forge/ We have made a short video that shows how to wire the ceramic K-type thermocouple CR-02 and connect it to the digital thermometer DM6801. I use some firebrick to simulate a kiln and show you that it can measure temperatures up to 1999 degree F.

https://youtu.be/_EWVBAVRgXM

]]> We have made a short video that shows how to wire the ceramic K-type thermocouple CR-02 and connect it to the digital thermometer DM6801. I use some firebrick to simulate a kiln and show you that it can measure temperatures up to 1999 degree F.

https://youtu.be/_EWVBAVRgXM

]]>