ESP8266 Node MCU v3 and LIKA SMAX-MB-PRG-L2 linear encoder: displacement measurement in IoT

Hi. I have got involved in a project at university about IoT. It is to involve sensing conventional machines and uploading data to a server using an ESP8266 Node MCU v3. The uploading of data to the server itself is trivial, but the problem arises when it comes to collecting data from the machines.
When it comes to temperatures, there is no problem here. A K-type thermocouple + Max31850 1-wire is enough for me to read temperatures up to 1200 degrees (I measure temperatures in ovens)

I have a problem when it comes to measuring displacements. My instructor came up with the idea that the measurement must be very accurate (0.1mm). In this case, only a linear encoder (preferably absolute) comes into play. The problem is that any encoders I find on the web require a minimum of 10V power supply, and my board runs on 3.3V (it has a 5V output powered from usb, but the logic runs on 3.3). I'm wondering if this can be jumped around somehow.

I found, for example, such an encoder LIKA SMAX-MB-PRG-L2
You can communicate with it via Modbus protocol via RS-485.

I would use a ready-made converter to switch from RS-485 to UART (for ESP8266).

The only problem is the unfortunate supply voltage. The encoder requires 10V. This may seem silly, but I would ask: what would happen if I connected a separate power supply to the sensor than to the board, of, say, 10V, and then used some sort of voltage divider for the logic?

Anyone have an idea how this problem could be solved?

studenciak214 wrote:

the only problem is this unfortunate supply voltage. The encoder requires 10V. This may seem silly, but I'll ask: what would happen if I connected a separate power supply to the sensor than to the board, of, say, 10V, and then used some sort of voltage divider for the logic?

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The idea is to convert the logic levels to 3V3? Maybe selecting a suitable converter from RS-485 to UART with 3V3 logic on the ESP side is enough (there are some on sale). What converter do you have at your disposal?
However, when it comes to powering the ESP, you can use a step-down converter from 10V to 3V3 with a load capacity of no less than 500mA. A resistor divider in this case is not a good idea, due to the unnecessary power lost on the resistors.

studenciak214 wrote:

The problem is that any encoders I find on the web require a minimum power supply of 10

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Have you seen an electronic caliper ? It is powered by a small watch battery. There are many off-the-shelf electronic rulers available that operate on an identical principle.

khoam wrote:

studenciak214 wrote:

the only problem is this wretched supply voltage. The encoder requires 10V. This may seem silly, but I would ask: what would happen if I connected a separate power supply to the sensor than to the board, of, say, 10V, and then used some sort of voltage divider for the logic?

.
The idea is to convert the logic levels to 3V3? Maybe selecting a suitable converter from RS-485 to UART with 3V3 logic on the ESP side is enough (there are some on sale). What converter do you have at your disposal?
However, when it comes to powering the ESP, you can use a step-down converter from 10V to 3V3 with a load capacity of no less than 500mA. A resistor divider in this case is not a good idea, due to the unnecessary power lost on the resistors.

I did some more searching and found the Pololu2595 - a logic state converter. The operating diagram looks more or less like this:
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All you need to do is provide the supply voltage for the sensor on one side, the esp on the other and short the grounds. I'm just wondering if it has to be the same power supply pushed through some kind of stabiliser, or if it can be 2 separate power sources. In other words, can I connect the ESP to a 3.3v power source and the sensor to a separate 10v power source and short the earths? What could be the consequences of doing this?

studenciak214 wrote:

I'm just wondering if it has to be the same power supply running through some kind of stabiliser, or if it could be 2 separate power supplies.

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They can be separate.

studenciak214 wrote:

In the sense, can I make it so that I connect the ESP to a 3.3v power source and the sensor to a separate 10v power source and short the grounds?

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You can short the grounds, and even should, if they are two separate power sources.