2020 Trade Shows are cancelled so let DYNOmite bring them to you...

Trade Show Update

10/28/2020

Trade Shows have been cancelled for 2020 and we are disappointed as you are. But in anticipation of this reality, we have been working hard to create a new-to-the-world virtual booth for our devoted Customers. You will hear more about this in the next weeks, but look for:

  1. Live streaming content with industry experts
  2. Demonstrations with service techs of our equipment
  3. Live chat with Sales and Service staff to discuss industry needs and innovations
  4. Watch as some of the most popular SuperFlow and DYNOMite products are being built
  5. the coolest opportunity the industry has ever experienced – YOUR chance to interact with our Innovation team to finalize versions of software and controls

DYNOmite views this year as an opportunity to engage with you in ways we haven't been able to in the past. Please visit our show page to register for additional information as it becomes available.

Thermocouple Errors


Understanding how these sensors work can help avoid invalid EGT readings.

Advanced | 07.28.20

STOP THERMOCOUPLE ERRORS…

by understanding how they work. TC’s are a reliable and inexpensive means of monitoring EGT during dyno testing. Yet, through seemingly innocent setup mistakes, it’s possible to skew their accuracy – inviting erroneous tuning decisions.

In 1821 Thomas Seebeck discovered that when a conductor (i.e. metal wire) is exposed to an end-to-end temperature change, it generates a tiny voltage. However measuring this voltage requires a junction from that wire to a meter (or DAQ), and both wires feel the same temperature differential, causing an inverse (canceling) voltage. The solution? A “thermocouple” junction using a dissimilar metal, one outputting different (non-canceling) volts per degree – leaving a signal to read.

A TC’s junction metals determine its voltage curve and “type”” The DYNOmite’s Type-K TC is Ni-Cr and Ni-Al alloy – generating about 0.022 Millivolts per Deg. F. with a working range to 2,200 degrees. Note: Substituting types requires custom gains and linearization. A TC’s voltage represents the temperature differential between its wires’ hot and cold ends. So, absolute readings requires knowing the cold junction’s temperature too. Lock that junction’s temperature (ice bath or fixed room temperature) and an offset calibrates the reading.

However, if a junction will experience large temperature changes within the dyno cell, then that junction’s temperature must be monitored and software offset compensated. The simplest thing is to keep the cold junction in a fixed 70 degree operator control room. If that requires extending the thermocouples leads, use only Type-K thermocouple wire and connectors. This avoids inducing new voltage generating junctions where the copper extension wires meet the Ni-Cr and Ni-Al metals.

When terminating the cold junction in an unstable temperature environment, use DYNO-MAX’s “User EGT Cold Junction Offset” formula to monitor temps and compensate. Contact DYNOmite Dynos tech support for more information on using this EGT Cold Junction Offset” formula.

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