Hello,
I am using a PV450 display and trying to use the 0-5vdc analog input. When I remove the signal to the input, the signal floats to an unsafe condition. Should there be a pull down resister to bring the signal back to 0v?

Thanks, please let me know.

Russell Tackett
High Country Tek, Sr, Field Applications engineer.
937-216-4669

Russell,
Sorry for the slow reply, I was out on vacation.

First, I assume you are using a PV450 model that includes the switchable analog input (resistive pull-up/0-5V/4-20mA). If that is the case, when the analog input is configured as a 0-5V input, the display assumes that there will be a 0-5V signal present at all times. This would include a 5V level signal from a pot, an externally powered sensor or perhaps an analog output from say an ECM. If there is no signal present, then the input will indeed float.

The design does not presently include any pull-down resistors after our buffer circuit and adding an external pull-down would most likely change the response curve of your input voltage.

Out of curiosity, what is the "unsafe condition" that you are referring to?

Scott Huhn
EControls Inc.
Senior Electrical Engineer - Displays
Office (210) 495-9772 x3821
Mobile (608) 201-5033
Email shuhn@econtrols.com
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