Samovar 7.00: the regulator type is selected on the "Regulator" («Регулятор») tab of the configurator: KVIC, RMVK, SEM_AVR or "Do not use" («Не использовать»).
WARNING!
All regulators connected to Samovar must be physically isolated in terms of voltage. These can be relays, optocouplers, data bus isolators such as ADUM, etc.
Never connect the regulators directly, otherwise the mains voltage will reach you and Samovar. The best thing that can happen in that case is that Samovar burns out.
Samovar supports several options. In Arduino IDE the choice is made with directives in Samovar_ini.h. In PlatformIO you can pick a ready-made environment: Samovar — KVIC, Samovar_rmvk — RMVK, Samovar_sem — SEM_AVR, Samovar_no_power — a build without a UART regulator. Only one option can be selected at a time.
Voltage regulators with UART protocol control
Algorithm for a regulator with UART.Turn-on: Samovar turns on relay No. 1 and waits for the time
SAMOVAR_USE_POWER_START_TIME (2000 ms by default; in the configurator it is "Regulator start delay, ms" («Задержка запуска регулятора, мс») on the "Regulator" tab; for SEM_AVR a further 3 s is allowed before that for the regulator to start), after which it sends the regulator the working command. If the regulator does not respond, heating is turned off with the message "Regulator command timeout" («Таймаут команды регулятора»). Relay No. 4 is controlled separately by the algorithm of the selected mode and does not have to turn on at the same time.
Turn-off: relays No. 1 and No. 4 are turned off immediately. After 700 ms the SLEEP command is sent to the regulator, and after another 200 ms the stop sequence ends.
Fully compatible with Samovar. The adjustment step on the encoder is 0.5 volt. Stabilization is 0.1 volt. It can be shut down in an emergency by an independent sensor.
2. Regulator RMVK (only versions No. 5 and 6 work with Samovar)
All RMVK models have power isolation on the control contacts by default, and no modification is needed to work with Samovar.
The adjustment step on the regulator and from Samovar is 1 volt. Stabilization is 1 volt. Version No. 6 can be shut down in an emergency by an independent sensor. Through the RMVK, Samovar fully controls the boost, stabilization and emergency shutdown of heating.
Warning! The RMVK works only with whole values, that is, it has an adjustment step of 1 volt, which has its own particularities when Samovar works in pre-flooding mode.
Compatible with Samovar. It has one particularity: in the Samovar interface the power delivered to the load is set and displayed not in volts (as with the previous two regulators) but in watts.
For correct operation with Samovar you need to use the sketch Stab-avr.ino, which comes with Samovar and is located in the directory ...Samovar\Stab-avr
Voltage regulators without external control over protocols.
For example:
RM2, RM2M, RM2-Pro (hereafter simply RM
) .
All RM models have power isolation on the control contacts by default, and no modification is needed to work with Samovar.
Control of these regulators comes down to two parameters:
- Turn the regulator itself on/off.
- Start/stop the "Boost" mode
The function is implemented with two relays whose contacts control the regulator. On Samovar's "Turn heating on" command,
the contacts of relay No. 1 turn the RM on. Relay No. 4 turns on the "Boost" mode only when the algorithm of the selected mode requires it.
Relay No. 4 opens its contacts and the RM turns off the boost mode. When the run is finished, Samovar turns the RM off with the contacts of relay No. 1.
Note:
- All the listed regulators work as standalone units and can be used with Samovar without a UART connection, following the principle and algorithm of the RM regulator.
Samovar and the voltage regulator show different power readings. How do I fix it?
By and large, the absolute power is not that important, but it is possible to get identical power readings on the regulator and on Samovar, and in essence there is only one method.
None of the regulators, Samovar included, measures power. They calculate it like calculators, from two values: the voltage currently applied to the heating element and the entered resistance value of that heating element.
The entered resistance is constant, and the voltage changes. The whole adjustment comes down to choosing the heating element resistance.
You can take the calculated resistance: the voltage squared divided by the power. The voltage is taken from the nameplate of the heating element. Example for a 3 kW, 220 volt heating element: 220*220/3000=16.13333333333 Ohm.
Or measure it with a multimeter.
For the RMVK regulators and the Simple one based on Chinese modules (Stab-avr).
Warning! If we are not actually going to heat the boiler, we disconnect the heating element.
- In the RMVK you can enter the power and voltage values, and the resistance is calculated automatically. Or enter the resistance and the power is calculated. Video on how to set it up. Watch it, do it, and do not forget to switch the regulator to the display in watts.
- In the Stab-avr, set the actual mains voltage at the moment with the potentiometer and enter the power value of your heating element.
Warning! The heating element power for the Stab-avr must be entered for a mains voltage of 230 volts. If the heater manufacturer gave the power for 220 volts in the datasheet, you need to recalculate it for 230 volts.
Start Samovar — heating. There is no point in adjusting anything in the Boost mode — the voltage will keep changing all the time, and the power with it. From Samovar, give the command to set some specific voltage on the regulator (say 170 volts for the RMVK, or 2000 watts for the Stab-avr). The regulators will switch to stabilization mode.
Compare the power values displayed in Samovar and on the regulator.
Now there are two ways — either change the resistance value in Samovar (web interface: MAIN page - Settings («ГЛАВНАЯ - Настройки») - Basic («Основные») - the Other («Прочие») tab), which is much more convenient. Or change the power value entered in the regulator. The goal is to get values on the regulator and in Samovar as close as possible.
The Kvic regulator .
It has no power readout. So only Samovar is adjusted, to the power you want to see…
That is the first option
This is convenient if different heating elements are used from time to time and/or the heating elements of the heating element assembly itself are switched.
The voltage and current meter really measures the current drawn and shows the actual power on its display. So if you want Samovar to show this power, just change the heater resistance value in Samovar on the fly.
See also:
