Joy-it StromPi 3 User manual

STROMPI 3
Power-Solution

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Pascalstr. 8 47506 Neukirchen-Vluyn
1. TABLE OF CONTENT
1. Table of content
2. General information
3. Overview
4. Power sources
5. QuickStart
6. Functions of the StromPi 3
6.1 Prioritisation of input
6.2 Time-controlled applications
6.2.1 Real Time Clock
6.2.2 Automatic configuration of time
6.2.3 Shutdown Timer
6.2.4 Alarm Modes
6.2.5 PowerO-Alarm Mode
6.2.6 WakeUp - Alarm Mode
6.2.7 Minute WakeUp-Alarm
6.2.8 Weekend WakeUp-Alarm
6.2.9 Interval Function
7. Additional functions
7.1 Serialless Mode
7.2 Example of usage with real time clock
7.3 PowerOn-Button Mode
7.4 Powero Mode
7.5 Power Save Mode
8. Configuration of StromPi 3
8.1 Activation of the serial communication
8.2 Execution of the GUI script
8.3 VNC for remote desktop connection
8.4 SSH-connection via PuTTY and Xming
8.5 SSH-connection via MobaXterm
9. StromPi 3 scripts
9.1 Serial scripts
9.2 Serialless scripts
9.3 Raspberry Pi Pin-Layout
9.4 Automatic execution of scripts
10. Modifications
11. Opening the serial console
12. Commands for the console
13. EU declaration of conformity
14. Further information
15. Support

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This manual is made for the firmware version 1.72. We
recommend upgrading the firmware of the StromPi regularly.
You can download the newest version of the firmware here.
There is a separate manual how to flash the firmware in the
download register.
2. GENERAL INFORMATION
Dear customer,
Thank you for purchasing our product. The structure and functions of the
StromPi3 are explained in the following chapters. We will show you
which settings should be made so that the Raspberry Pi will work
smoothly with the StromPi.
If you have any diiculties with the usage of the device, do not hesitate to
contact us.
The StromPi 3 enables the Raspberry Pi® and other single-board
computer new areas of application. Additionally, the StromPi 3 has an
optional plug-in unit for batteries besides the same voltage inputs as the
StromPi2 (mUSB, WideRange 6-61V). This expands the Raspberry with a
LiFePO4 battery which is a rechargeable emergency power source.
Unexpected power failures are now in the past!
The prioritized inputs can easily be changed which means the StromPi 3
will fit perfectly into your project. With the voltage range from 6V to 61V
and a current with up to 3A, there is enough power for even bigger pro-
jects. In addition, the StromPi 3 has an own configurable, autonomously
operating microsystem unit which can be used for a programmable start-
stop behaviour:
Let your system boot and shut down at pre-set times to do
measurements or to switch devices on and o (ideal for digital signals or
for controlling machines). The included real time clock can be used to
synchronize the time of the Raspberry Pi without internet access. There is
also an expansion to control the serial interface (state battery charge,
voltage of the in-/ outputs, control and configuration) which makes the
StromPi3 to an absolute allrounder.
The StromPi 3 is perfectly suitable for every application area!

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3. OVERVIEW
GPIO port
LiFePO4 battery
high - power
USB output
data input (for high-
power USB output) &
current output
microUSB - voltage input
switch
capacitor - buering
wide-range
voltage input
With heavy load the StromPi 3 can heat up. Do not ouch the
circuit board during operation to avoid burns. Also allow a good
supply of air to prevent the unit from overheating.

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4. POWER SOURCES
The StromPi 3 can get its power from three dierent power sources. In
case of a power failure, it switches to the power source which is configu-
rated as the second and if necessary to the third.
microUSB
The StromPi 3 can of course, as usual, be powered via the microUSB port.
Wide - Range
The Wide mode can be used with a voltage source from 6V - 61V. Connect
the marked port to an arbitrary voltage source, like a power supply or a
vehicle electrical system.
Attention! The voltage source must be switched on within the range of
6 - 61 V. Please pay attention to the polarity to avoid damaging the
Raspberry Pi or the StromPi3.
Battery unit
The StromPi 3 can be expanded with an optional 1000 mAh or 2000 mAh
LiFe04 battery, which is a rechargeable emergency power source. You
only have to plug in the separately available battery unit, which then can
be configurated as the second or third current source. Because of the
implemented GPIO-bar on the battery unit, you do not have any restric-
tions with the usage of it.
If the orange LED on the battery unit lights up,
it means the battery is charging.
If the LED flashes, it is an indication
that the battery unit is defective.
In order to be able to use all functions of the
StromPis to the full extent, you must use our Python
scripts. These are listed and explained in chapter 9
StromPi 3 scripts.

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5. QUICKSTART
In this chapter, you will find the necessary steps to use the StromPi 3.
Activation of the serial communication
More details can be found in chapter 8.1
Use the following commands to install the required dependencies and
then open the file config.txt .
sudo apt-get update
sudo apt-get install python-serial python3-serial
sudo nano /boot/config.txt
Now append the following lines to the end of the file:
dtoverlay=pi3-miniuart-bt
enable_uart=1
core_freq=250
Open the Raspberry configuration and disable in
5 Interfacing Options → P6 Serial the serial login shell and activate
the serial hardware.
Opening of the serial console
More details can be found in chapter 11
Use the following commands to install Minicom and connect the
Raspberry Pi to the StromPi 3.
sudo apt-get update
sudo apt-get install minicom
sudo minicom -D /dev/serial0 -b 38400
Open the console of the StromPi 3 with the following command :
(the typed characters are not displayed)
startstrompiconsole
- ... or the shortcut:
sspc
The command show-status opens the current configuration setting and
help gives you an overview of the commands.
The start screen of the StromPi 3 console looks like this:

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6. FUNCTIONS OF THE STROMPI 3
①Choose the StromPi V3 Powerpath Mode
②Enable or disable the Powerfail Warning
③Adjust the Battery Shutdown Mode
④Enable or disable the Serialless Mode
⑤Enable or disable the Power Save Mode
⑥Enable or disable the Powero Mode
⑦Adjust the Alarm Mode
⑧Adjust the WakeUp-Alarm Mode
⑨Adjust the PowerO-Alarm Mode
⑩Adjust the Interval - Alarm Mode
⑪Adjust the Real Time Clock
⑫Enable or disable the Shutdown-Timers and adjust the time
(in seconds)
⑬Enable or disable the PowerOnButton and adjust the time (in sec-
onds)
①
②
③
④
⑤
⑥
⑦
⑧
⑨
⑩
⑪
⑫
⑬
A serial connection is required to make all settings described in
the following chapters. Chapter 8 explains how to configure the
serial port for the Raspberry Pi.

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StromPi V3 Powerpath Mode:
The StromPi V3 Powerpath Mode determines the prioritisation of the
separate voltage sources.
Powerfail Warning Mode:
The PowerFail Warning Mode will warn in case that the prioritised voltage
source is failing.
Battery Shutdown Mode:
The Battery Shutdown Mode determines at which battery charge level the
Raspberry Pi should be shut down.
Serialless Mode:
The Serialless Mode allows using the serial ports for other purposes by
communicating via a GPIO pin. [Modification required! see chapter 10
Modifications].
Power Save Mode:
The Power Save Mode will reduce the power consumption if Wide is set up as
the secondary power source. However, this is only recommended when the
device is in operation with a low amperage (<2,5A / for example an
Raspberry Pi without periphery).
Real Time Clock Settings:
In the RTC settings, you can set up the time and the date of the real time
clock manually or automatically with comparing and synchronising the time
with the Raspberry Pi.
Shutdown Timer:
If you have activated the Shutdown Timer and the StromPi detects a power
failure at the primary power source, the StromPi3 will send a signal to the
Raspberry Pi through the serial interface to start the shutdown (according to
the script). Aer the counter has expired, the StromPi 3 will disconnect the
power supply of the Raspberry Pi.
PowerOnButton:
With the PowerOnButton, you can restart the switched o Raspberry Pi by
closing the contact between the reset pins. [Modification required! See
chapter 10 Modification].
Interval Timer:
The interval timer can be set up to shutdown or boot the system aer a
selected time.
Alarm Mode:
The alarm mode refers to the WakeUp-Alarm and PowerO-Alarm Mode. It
selects if the alarm goes o daily, weekly or only at a specific date.
WakeUp-Alarm Mode:
The WakeUp-Alarm Mode starts the Raspberry Pi at a specific time.
PowerO -Alarm Mode:
The PowerO-Alarm Mode shuts down the Raspberry Pi at a specific time.
Powero Mode:
The Powero Mode requires the Raspberry Pi to be switched on with the
PowerOnButton aer a shutdown by the ShutDown Timer. Additionally, the
Powero Mode prevents detection if the primary power supply returns.

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6.1 Prioritisation of input
The voltage source from which the StromPi 3 obtains its energy can be
adjusted according to your wishes and the intended use.
In addition, a second or even a third voltage source can be selected,
which automatically takes over the supply in case the first source should
fail.
The factory setting is configured so that the microUSB input serves as the
main power source. If this fails, the wide-range input is automatically ad-
ded as an alternative source.
In total there are six dierent modes possible. The primary power source
is the main power source. The secondary power source will take over
when the primary source fails.
MODE PRIMARY SECONDARY TERTIARY
Mode 1 microUSB Wide - Range -
Mode 2 Wide - Range microUSB -
Mode 3 microUSB battery -
Mode 4 Wide - Range battery -
Mode 5
(from version 1.6 on)
microUSB Wide - Range battery
Mode 6
(from version 1.6 on) Wide - Range microUSB battery
You can set the corresponding mode via the config script under "Choose
StromPi V3 Powerpath Mode".
Automatic change of power sources
due to primary source failure
Primary power source
failure
Prim. Source
active Sec. Source ready
Prim. Source
failed
Sec. Source
active

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6.2 Time-controlled applications
6.2.1 Real Time Clock
The StromPi 3 also has a real-time clock. Should the power fail,
even time-controlled applications are not endangered.
Time controlled starts and shutdowns of the Raspberry Pi is
also not a problem!
Please note that for continuous operation of the RTC at least
one of the power sources (mUSB, Wide Range or battery) must
remain connected to the StromPi 3. If all power sources are
disconnected, the current time is not stored.
The real time clock (RTC) of the StromPi 3 can be set with the config
script:
Setting the time and date manually
To set the time and date manually, click on Manual Setting. Now, you can
enter the time and date in the corresponding fields to the right side. Click
on Update to apply the settings.
Synchronise time and date with the Raspberry Pi
To synchronize the time and date with the Raspberry Pi, click on Sync
with RaspberryPi. Clicking on Update compares the time of the RTC of the
StromPi with the Raspberry Pi. The older time is overwritten with the
more recent one. The pre-set time of the StromPi is the 01. May 2018 and
the Raspberry Pi updates its time when it is connected to the Internet.
6.2.2 Automatic configuration of time
In addition, we provide a script which synchronises the time aer the
boot of the Raspberry. This script can be downloaded here in the section
„Scripts“. Download the archive, unzip and copy the script to your Rasp-
berry Pi.
In chapter 9.4 Automatic execution of scripts, you can read how to add
scripts to the Autostart so that they perform automatically aer a boot.

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6.2.3 Shutdown Timer
The StromPi 3 has a shutdown timer which automatically interrupts the
power supply of your Raspberry Pi aer a failure of the primary power sup-
ply is detected. You can choose the period of time, when the shutdown
takes place aer the failure of the power supply, individually, according to
your needs. For example, if you have set the shutdown timer to 600 (600
seconds -> 10 minutes), the system operates like the following:
If the StromPi 3 now detects a power failure, the timer starts. Aer 10
minutes the StromPi 3 will then disconnect the power supply to the
Raspberry Pi. Additionally, we provide a script that can detect a power
failure either via the serial console or via a GPIO pin and then shut down
the Raspberry Pi safely. The shutdown timer can be set in the config
script by Shutdown Timer.

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To enable the Shutdown Timer, select Enable at Choose Shutdown
Mode and enter the desired shutdown time in seconds into the adjacent
field. Finally, confirm with Update.
6.2.4 Alarm Modes
The StromPi3 has the possibility to start and shut down the Raspberry
time-controlled. With the combination of WakeUp-Alarm and
PowerO-Alarm Mode, you can configure an individual start-stop
behaviour for your Raspberry Pi (e.g. start at 10:45 every day and shut
down at 13:00 ).
Your Raspberry Pi will only be active during the time window in which
the incurring tasks have to be completed.

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6.2.5 PowerO - Alarm Mode
The PowerO alarm allows you to use the Raspberry Pi every day at a
preset time. However, the Raspberry Pi can only be shut down once a day
using this mode.
If you want to shut down the StromPi3 time-controlled, start the config
script.
Switch Choose PowerO-Alarm Mode to Enable to activate the
PowerO-Alarm. Enter the time when the Raspberry Pi should be shut
down into the two fields on the right side. Enter the minutes in the field
Choose Power-O Minutes and the hours in the field Choose Power-O
Hours.
6.2.6 WakeUp - Alarm Mode
The WakeUp-Alarm allows you to start the Raspberry time-controlled. In
addition, you have the possibility to activate these functions for a specific
date or a weekday.
If you want to start the StromPi 3 time-controlled, start the config script.
Switch Choose WakeUp-Alarm Mode to Enable to activate the
WakeUp-Alarm. Enter the time, when the Raspberry Pi should start, in the
two fields to the right side. Enter the minutes in the field Choose WakeUp
-Alarm Minutes and the hours in the field Choose WakeUp-Alarm hours .
The Raspberry Pi can only be started once a day using this mode.

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Depending on what you have set in Choose Alarm Mode , your Raspberry
Pi will now boot daily, weekly or just at a set date at the set time. With
Alarm Mode 1, your Raspberry starts at the set time every day. With Alarm
Mode 2, your Raspberry starts on a specific date at the time you set. With
Alarm Mode 3, your Raspberry will start at the specific weekday you set
once a week. With Alarm Mode 4 you activate the Minute WakeUp Alarm.
The alarm mode refers exclusively to the WakeUp-Alarm, it has no influ-
ence on the PowerO-Alarm.
Attention! Your Raspberry Pi can only be started via the
WakeUp-Alarm if it was previously shut down automatically via
the PowerO-Alarm or it was shut down manually with the
serial command powero .
6.2.7 Minute WakeUp-Alarm Mode
The Minute WakeUp Alarm allows you to set an automatic timer, to start
the Raspberry Pi aer the Raspberry Pi has been switched o by the
PowerO command or the PowerO-Alarm. This timer is given in
minutes. To activate this mode, the alarm mode must be set to Minute
WakeUp-Alarm in the config script.
The time must then be set (specified in minutes):
6.2.8 Weekend WakeUp-Alarm
The Weekend WakeUp-Alarm allows you to switch the WakeUp-Alarm on
or o during the weekend. If you set this mode to Disabled, the StromPi 3
will be switched o during the weekend (Saturday and Sunday) and will
not be launched by the WakeUp-Alarm. If you continue to start the
Raspberry Pi with the WakeUp-Alarm during the weekend, the
WakeUp-Alarm must be set to Enabled.

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6.2.9 Interval Function
The interval function allows you to define time intervals in which the
Raspberry Pi is switched o and on again with the help of the StromPi
3.You can activate and configure this function in the config script by
Timer.
Switch Choose Interval-Alarm Mode to Enable to enable the Interval func-
tion.
At Interval On-Time in minutes, you can set the time that the Raspberry Pi
should remain on in minutes.
At Interval O-Time in minutes , you can set the time that Raspberry Pi
should remain o in minutes.

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7. ADDITIONAL FUNCTIONS
7.1 Serialless Mode
The Serialless Mode allows you to suppress any serial communication of
the StromPi, you can e.g. use another HAT, which uses the serial inter-
face, can be used simultaneously with the StromPi. However, this also
prevents the StromPi 3 from being configured, which is why it is useful to
configure the StromPi before you activate the Serialless Mode.
In addition, this mode causes that the shutdown warning is not transmit-
ted via the serial interface as before, but via a free GPIO pin.
To activate the Serialless Mode, you have to set the Serialless Mode in the
config script by under Choose Serialless Mode to Enable.
You must also run the Start_Serialless.py script.
When you have done this, the Serialless Mode is activated and the serial
communication is now completely suppressed. To end the Serialless
Mode again, you have to execute the script Stop_Serialless.py . This script
sets the GPIO pin to low if the GPIO pin is on low for more than 5
seconds, the Serialless Mode is deactivated again.
For this mode the Serialless - modification is necessary which is
described in detail in chapter 10 Modifications.
The scripts used here require Python3.
7.2 Example of usage with real time clock
Now to show you one of the many possible applications, we have created
a script ( RTCSerialless.py ) which aer starting the script, deactivates the
Serialless Mode, then synchronizes the real time clock, and activates the
Serialless Mode again. Here is the console output aer successful execu-
tion of the scripts:

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7.3 PowerOn-Button Mode
The PowerOn-Button Mode allows the StromPi to be started again aer
shutdown with the powero command or the PowerO-Alarm without
disconnecting the power supply or removing the BatteryHATs.
Only a small modification is necessary for this function. A cable bridge
must be soldered in between two solder pads. Then it is possible to re-
start the StromPi 3 by bridging the reset pin.
If the StromPi 3 is already modified for the Serialless Mode or used in
Serialless Mode with the PowerOn-Button modification a further small
modification must be made.
In chapter 10 Modifications, we will explain exactly what is required.
IMPORTANT: The set time in the configuration script is the initi-
alizsation of the PowerOn-Button. We recommend a time of at
least 30 seconds.
7.4 Powero Mode
The Powero Mode ensures that aer a power failure your Raspberry Pi
remains switched o until you press the PowerOn-Button
(see chapter 7.3).
You lose the option of recognising a powerback so that the Raspberry will
shut down in any case and the StromPi will switch o the power supply to
the Raspberry aer the set time. To switch on the Powero
Mode, you must set Choose Powero Mode in the config script to Enable.

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7.5 Power Save Mode
The Power Save Mode allows you to drastically reduce the power
consumption of the StromPi 3 by switching o the voltage converter
when the Wide port is not in use and switching it only on in case of a
power failure of the primary power supply. This is only possible in low
current mode (below 2.5 A).
If the current is too high, there could be complications when switching
the power paths.
To activate the Power Save Mode, the jumpers are set OFF as shown in
the following picture.
Additionally, you have to set Choose Power Save Mode to Enable in the
config script.
8. CONFIGURATION OF STROMPI 3
Here, we show you how to set up the serial communication for the
StromPi. This manual is based on Raspbian Buster from December 2019.
We recommend that you use the latest version of the Raspbian Buster
image.

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8.1 Activation of the serial communication
In order to use the functions of the StromPi and to make settings, a few
adjustments must be made to your Raspberry Pi.
First, you need to install the Python3-Serial library by typing the follo-
wing command into the console of the Raspberry Pi:
sudo apt-get install python-serial python3-serial
Then open the console on your Raspberry Pi and enter
the following command:
sudo nano /boot/config.txt
Append the following lines to the end of the file:
dtoverlay=pi3-miniuart-bt
enable_uart=1
core_freq=250
Save the file with the key combination Ctrl+O and exit the file with the
combination Ctrl+X.
In addition to this, it is necessary to activate the serial port of the Rasp-
berry Pi and deactivate the serial console. You can do this either via the
Raspberry Pi Configuration or via the Raspi-Config .
To do this via the Raspi-Config , enter the following command into the ter-
minal window on your Raspberry Pi :
sudo raspi-config

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Use the arrow keys on your keyboard to navigate to menu 5 Interfacing
Options.
Select the point P6 Serial.
The question Would you like a login shell to be accessible over serial?
answer with No.
The question Would you like the serial port hardware to be enabled?
answer with Yes.