This is the Photo of a RTD 3-W Mains Powered Temperature 4-20mA Transmitter. The Circuits and PCB are here RTD PT100 Transmitter and Multiplexer.
From Soldermans Basic Electronics
Now with new Technologies like Zigbee and Modbus, We can classify Transmitters as shown below. The Measured Parameter Temperature, Flow or Events Has to reach an Intelligent Data Storage [...]
This is part of an user manual i used to give for cooling controllers – app007.pdf
The Logic of cooling in temperature control is inverted, Activating the relay powers a compressor which cools the system. A small modification at the output stage, makes any heating controller into a cooling controller. It can also be done with [...]
This is a RTD Pt-100 Transmitter, It can Convert Thermocouple mV or RTD mV to 4-20 mA Current Transmitter. The part numbers on Circuit and silk screen may not match. But the PCB may be usable. The output is a current source and not a current sink. It goes to a 4-20mA Mux with a [...]
These are the circuits and boards of a Mini Temperature Transmitter for a Platinum hundred ohms temperature Sensor. RTD-3W-Transmitter Circuit. See my Transmitter Application Note for this. The customer wanted a two wire system, this needs low power opamps which were ten times the price. If this transmitter works at 3mA it could have [...]
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