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Table of Contents

Can I …?

How can I implement an Emergency stop on the RevPi

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Can I use a temperature sensor with Node-RED?

Yes, for example with a 1Wire USB bus coupler and the DS9490R from ESRA, which is listed here as tested:

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Can I get the 14-pin connector of the DIO module?

Our connector in the color gray is a special production. The same connector in black or green is available from Phoenix Contact.

Can I operate a thermocouple on a Revolution Pi module, i.e., an AIO module?

  • No, unfortunately not.

Can I expand the RevPi's internal memory with an SSD or NVMe?

We do not currently offer memory expansion on any of our units except via USB.

→ Related to Core 1/3/3+/SE/S, Connect 3/3+/SE/S, Flat, Compact

Can I destroy modules in a hardware setup because of a short circuit?

In a hardware setup with several IO modules and a Revolution Pi Connect SE module, a short circuit occurred at power up. I should mention that at the time of the damage to the IO modules, a USB cable was attached to put the controller into bootloader mode to read the disk image, so I was thinking maybe the cable was defective. However, I tested the cable OK on other devices and it seems to be fine. How can this be?

  • The Revolution Pi Connect SE module works and is not affected by the polarity reversal because it has a galvanically isolated power supply.

  • If individual IO modules are connected with reversed polarity, this can lead to destruction.

  • Take a look at Video Tutorial #12 – Controlling the Digital IO Modules with the PiBridge. There it is explained why a short circuit can occur due to the polarity reversal of individual modules. https://revolutionpi.com/tutorials/video-tutorials/#VT12

  • It certainly couldn't be the USB cable. A USB2 port does not bring the current that would be needed, USB2 sources shut down at more than 500mA, except chargers and power packs. So, no, a IO module was incorrectly polarized.

Can I experiment with the RevPi stretch image on a standard Raspberry Pi 3b+?

No, because the image was adapted to the RevPi hardware.
In the GitHub repository are all the sources to make adjustments and, if necessary, adapt the image according to your needs.

https://revolutionpi.de/forum/viewtopic.php?f=6&t=2715#p9876

Can I operate a second RevPi Con CAN module?

No, unfortunately, it is not possible to maintain more than one RevPi Con CAN module.

https://revolutionpi.de/forum/viewtopic.php?f=4&t=2705

Can I use 868 MHz with a LoRa antenna?

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Would it be possible to connect a 3-wire PT100 to the analog inputs of a RevPi Compact?

  • The RevPi Compact does only support 2 wire PT100 RTD, which must be connected to an input, and it's 0V pendant.

  • If the sensor is only available as a 3 or 4 wire variant, you could use an external temperature transducer (converts the RTD to 0-10 V / 4-20mA)

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Can I put a CM4S in a Revolution Pi Compact Module?

  • No, unfortunately the CM4S it is incompatible.

Can I use the 3 unlabeled LEDs on the DIO module?

No, they are not assembled on the circuit board.

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Can I use PTP Time Stamps?

Yes, take a look here:

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Can I use absolute encoders?

Currently, the Revolution Pi's "Encoder" option primarily supports incremental encoders.

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How can I implement an Emergency stop on the RevPi

take a look at the following link : https://revolutionpi.com/forum/viewtopic.php?t=3851

Can I get the 14-pin connector of the DIO module?

Our connector in the color gray is a special production. The same connector in black or green is available from Phoenix Contact.

Can I operate a thermocouple on a Revolution Pi module, i.e., an AIO module?

  • No, unfortunately not.

Can I expand the RevPi's internal memory with an SSD or NVMe?

We do not currently offer memory expansion on any of our units except via USB.

→ Related to Core 1/3/3+/SE/S, Connect 3/3+/SE/S, Flat, Compact

Can I destroy modules in a hardware setup because of a short circuit?

In a hardware setup with several IO modules and a Revolution Pi Connect SE module, a short circuit occurred at power up. I should mention that at the time of the damage to the IO modules, a USB cable was attached to put the controller into bootloader mode to read the disk image, so I was thinking maybe the cable was defective. However, I tested the cable OK on other devices and it seems to be fine. How can this be?

  • The Revolution Pi Connect SE module works and is not affected by the polarity reversal because it has a galvanically isolated power supply.

  • If individual IO modules are connected with reversed polarity, this can lead to destruction.

  • Take a look at Video Tutorial #12 – Controlling the Digital IO Modules with the PiBridge. There it is explained why a short circuit can occur due to the polarity reversal of individual modules. https://revolutionpi.com/tutorials/video-tutorials/#VT12

  • It certainly couldn't be the USB cable. A USB2 port does not bring the current that would be needed, USB2 sources shut down at more than 500mA, except chargers and power packs. So, no, a IO module was incorrectly polarized.

Can I experiment with the RevPi stretch image on a standard Raspberry Pi 3b+?

No, because the image was adapted to the RevPi hardware.
In the GitHub repository are all the sources to make adjustments and, if necessary, adapt the image according to your needs.

https://revolutionpi.de/forum/viewtopic.php?f=36&t=27492715#p9876

Can

...

Well, that depends on whether you are willing to invest time and effort in the implementation.

The PiBridge interface and the PiControl driver are documented here:

I operate a second RevPi Con CAN module?

No, unfortunately, it is not possible to maintain more than one RevPi Con CAN module.

https://revolutionpi.

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de/

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forum/

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viewtopic.php?f=4&t=2705

Can I use 868 MHz with a LoRa antenna?

More or loss – take a look at Using ISM Interface for Wireless M-Bus.
There is unfortunately no process image integration out of the box. But you are free to implement it yourself.

https://revolutionpi.

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de/

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Can I order the necessary clamps with you? I want to panel mount the Faytech monitor.

No, unfortunately not. Please contact Faytech forum/viewtopic.php?f=3&t=2749

Can the DIO module also be connected to other hardware, like the Raspberry Pi 4B?

Well, that depends on whether you are willing to invest time and effort in the implementation.

The PiBridge interface and the PiControl driver are documented here:

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What can I do when no picture appears on the HDMI screen although the power LED is on?

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Can I order the necessary clamps with you? I want to panel mount the Faytech monitor.

No, unfortunately not. Please contact Faytech here:
https://www.faytech.com/product/accesso ... -brackets/

What can I do when no picture appears on the HDMI screen although the power LED is on?

Do you have a micro USB cable connected? Please remove it and restart your RevPi by disconnecting it briefly from the power supply. Then it will boot normally again.

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https://revolutionpi.de/forum/viewtopic.php?f=18&t=3118

Is there …?

Would it be possible to operate the IO cards remotely with a cable between the RevPi base module?

Yes, you have to realize this yourself, for example with a maker set:

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The RS485 interface of the PiBridge sometimes delivers a strange signal. It is not rectangular formed, is this normal?

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Others Questions…?

Is it possible to replace a compute module?

  • Yes, see here

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How can you meet the EMC with a plastic enclosure?

We generally always have plastic housings without additional shielding. Additional shielding is normally not required with proper hardware design. The immunity complies with EN 61000-6-2 Immunity standard for industrial environments.

What are the voltage ranges in which a logical high signal and logical low signal are recognized?

Our production requires that the real-time performance of the RevPi can reach 10us, can it be achieved? If not, what is the highest real-time performance of the RevPi?

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What is the use-case for the SYNC pin on the RevPi Connect 4?

The SYNC pin was actually intended for TSN but this is no longer an issue.

(659) pibridge sync pin use-case? - The Industrial Raspberry Pi Forum (revolutionpi.com)

What is the meaning of the RS485ErrorCnt variables?

This is where transmission errors are counted on the PiBridge backplane bus. If the transmission errors exceed a value, the PiBridge is switched off. This brings the IO modules into a safe state.

(666) RS485ErrorCnt in RevPi Core S - The Industrial Raspberry Pi Forum (revolutionpi.com)

One of the black plastic clips that secures the PLC to the DIN Rail broke. Is it possible get a replacement?

Well, there is no such part number and I can understand you, so what can we do here? You can buy this thing called Maker-Set.

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Is it possible to replace a compute module?

  • Yes, see here

...

How can you meet the EMC with a plastic enclosure?

We generally always have plastic housings without additional shielding. Additional shielding is normally not required with proper hardware design. The immunity complies with EN 61000-6-2 Immunity standard for industrial environments.

What are the voltage ranges in which a logical high signal and logical low signal are recognized?

...

Original discussion

https://revolutionpi.de/forum/viewtopic.php?f=3&t=3057#p11037

What is the upper limit on leakage current in digital outputs in RevPi DO when operated at 12V?

  • The leakage current is max. 20µA.

What is the RJ11 pin assignment of the RevPi Flat?

What size circuit breaker would you recommend for the power supply for the RevPi?

To protect the power supply, you need to read the data sheet of the power supply you are using and see what they recommend. Our RevPi can be protected with a 2A fuse (fine-wire).

I want to write x MB/day to the eMMC, what is the lifetime using an ext4 file system?

Samsung's eMMC components are installed in the Compute Module. Samsung does not specify the number of erase/write accesses for the chip in the data sheet, nor a lifetime in operating hours. Typically, eMMC has a guaranteed lifetime of approx. 10,000-30,000 write accesses for each individual cell. Experience shows that the real achievable cycle numbers of flash memories are significantly higher – due to the wide range of controller technologies used with wear levelling etc. According to the data sheet, the Samsung eMMC has a flash transition layer with wear levelling, bad block management and ECC. How far you can get without data loss is very difficult to calculate… We do not know of any failures with it so far.

The form factor of the Revolution Pi Core / Connect devices is a bit too high for my control cabinet, are there any alternatives?

The RevPi Core 3+ and RevPi Connect+ with the associated expansion modules and gateways are designed for the typical form factor in industrial control cabinets.

For use in home sub-distribution panels, we tend to see the RevPi Compact (https://revolution.kunbus.de/revpi-compact/) or the RevPi Flat (https://revolution.kunbus.de/revpi-flat/). They have the appropriate form factor for this.

There are two different versions of the RevPi Connect Module, what are the differences?

  • The "PR100304R00 - 1.0 version" contained two power supply modules. These were combined in the "PR100304R01 - 1.1 version" into one galvanically isolated power supply unit. For this reason, the 8-pin X4 connector (at the bottom of the RevPi Connect) has been changed to a 4-pin connector. The bridge for the watchdog is still pre-assembled.

  • The RS485 interface is now galvanically isolated with version “PR100304R01 – 1.1 version”.

The power supply unit is not included in the scope of delivery, which one should I use?

We recommend the following power supply unit from our shop:

https://revolution.kunbus.de/shop/en/netzteil-meanwell-hutschiene-mdr-60-24

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Our production requires that the real-time performance of the RevPi can reach 10us, can it be achieved? If not, what is the highest real-time performance of the RevPi?

It depends on what you want to control. If you would like to control devices connected via the PiBridge you can read the performance of the PiBridge.
Look at the variable RevPiIOCycle: https://revolutionpi.com/pictory-neues-revpi-core-v1-2-jessie/?noredirect=en_US
But the value is in the MS range.
The only exception is the RevPi Compact module, which is not modular and therefore has a much higher performance: https://revolutionpi.com/tutorials/digitale-ein-und-ausgaenge-compact/

Original discussion

https://revolutionpi.de/forum/viewtopic.php?f=3&t=3057#p11037

What is the upper limit on leakage current in digital outputs in RevPi DO when operated at 12V?

  • The leakage current is max. 20µA.

What is the RJ11 pin assignment of the RevPi Flat?

What size circuit breaker would you recommend for the power supply for the RevPi?

To protect the power supply, you need to read the data sheet of the power supply you are using and see what they recommend. Our RevPi can be protected with a 2A fuse (fine-wire).

I want to write x MB/day to the eMMC, what is the lifetime using an ext4 file system?

Samsung's eMMC components are installed in the Compute Module. Samsung does not specify the number of erase/write accesses for the chip in the data sheet, nor a lifetime in operating hours. Typically, eMMC has a guaranteed lifetime of approx. 10,000-30,000 write accesses for each individual cell. Experience shows that the real achievable cycle numbers of flash memories are significantly higher – due to the wide range of controller technologies used with wear levelling etc. According to the data sheet, the Samsung eMMC has a flash transition layer with wear levelling, bad block management and ECC. How far you can get without data loss is very difficult to calculate… We do not know of any failures with it so far.

The form factor of the Revolution Pi Core / Connect devices is a bit too high for my control cabinet, are there any alternatives?

The RevPi Core 3+ and RevPi Connect+ with the associated expansion modules and gateways are designed for the typical form factor in industrial control cabinets.

For use in home sub-distribution panels, we tend to see the RevPi Compact (https://revolution.kunbus.de/revpi-compact/) or the RevPi Flat (https://revolution.kunbus.de/revpi-flat/). They have the appropriate form factor for this.

There are two different versions of the RevPi Connect Module, what are the differences?

  • The "PR100304R00 - 1.0 version" contained two power supply modules. These were combined in the "PR100304R01 - 1.1 version" into one galvanically isolated power supply unit. For this reason, the 8-pin X4 connector (at the bottom of the RevPi Connect) has been changed to a 4-pin connector. The bridge for the watchdog is still pre-assembled.

  • The RS485 interface is now galvanically isolated with version “PR100304R01 – 1.1 version”.

The power supply unit is not included in the scope of delivery, which one should I use?

We recommend the following power supply unit from our shop:

https://revolution.kunbus.de/shop/en/netzteil-meanwell-hutschiene-mdr-60-24

Of course, you can also use another 24 V power supply unit, but make sure that the 24 V is applied < 30 ms; otherwise an error may occur with other modules.

https://revolution.kunbus.de/forum/viewtopic.php?f=3&t=1655&p=6759&hilit=ramp+up#p6759

I would like to use encoders, what to consider?

Hardware options

  • DI/DIO/MIO-Module plus Revolution Pi Core or Revolution Pi Connect

  • Revolution Pi Compact Module

Configuration options

...

I would like to use encoders, what to consider?

Hardware options

  • DI/DIO/MIO-Module plus Revolution Pi Core or Revolution Pi Connect

  • Revolution Pi Compact Module

Configuration options

I need details about PiBridge communication and pinout for a project. Where can I find details?

I need details about PiBridge communication and pinout for a project. Where can I find details?

Are there alternative plug connections for the PiBridge, e.g. a cable connection?

No, this is not being developed. You are welcome to develop your own alternative connector, but we will not guarantee interference-free communication via the PiBridge. Keyword: EMC, length of cable, signal quality, (There is a reason why "only" up to 5 modules can be attached on each side).

Has the RevPi Compact been certified and tested according to the EN 61000-6-3 standard, which is necessary for the B2C market?

  • Yes, according to the EMC test report. However, we only issue this report upon request.

The RevPi Connect watchdog LED is lighting green. Does this mean the Watchdog is enabled?

The hardware watchdog time on the RevPi Connect is different when switching on the system, right?

Yes, when switching on the system, there is a "startup delay time", this is between min. 60s and max. 180s.
After this time comes the actual "watchdog timeout period", which is also min. 60s and max. 180s.
So the first time (power up) the times add up, after that only the timeout period time is left.
More details can be found in the datasheet of the watchdog module MAX6370:

https://www.maximintegrated.com/en/products/power/supervisors-voltage-monitors-sequencers/MAX6370.html

We want to use the RevPi water and dust protected in an IP66 housing. Any experience with overheating when there is minimal space around the RevPi?

...

Are there alternative plug connections for the PiBridge, e.g. a cable connection?

No, this is not being developed. You are welcome to develop your own alternative connector, but we will not guarantee interference-free communication via the PiBridge. Keyword: EMC, length of cable, signal quality, (There is a reason why "only" up to 5 modules can be attached on each side).

Has the RevPi Compact been certified and tested according to the EN 61000-6-3 standard, which is necessary for the B2C market?

  • Yes, according to the EMC test report. However, we only issue this report upon request.

The RevPi Connect watchdog LED is lighting green. Does this mean the Watchdog is enabled?

The hardware watchdog time on the RevPi Connect is different when switching on the system, right?

Yes, when switching on the system, there is a "startup delay time", this is between min. 60s and max. 180s.
After this time comes the actual "watchdog timeout period", which is also min. 60s and max. 180s.
So the first time (power up) the times add up, after that only the timeout period time is left.
More details can be found in the datasheet of the watchdog module MAX6370:

https://www.maximintegrated.com/en/products/power/supervisors-voltage-monitors-sequencers/MAX6370.html

We want to use the RevPi water and dust protected in an IP66 housing. Any experience with overheating when there is minimal space around the RevPi?

https://revolutionpi.de/forum/viewtopic.php?f=4&t=2585#p9695

Would like to know what the consequences would be of operating a RevPi at a higher temperature than, i.e. 55°C?

The Compute Module inside the Revolution Pi devices has different thresholds according to the ambient temperature to automatically down clock the CPU frequency.

Here is a link to the data sheet of the Compute Module 4:

Among other things, it says this

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