Thanks for your quick reply.
Czy wolisz polską wersję strony elektroda?
Nie, dziękuję Przekieruj mnie tam
luxmcdiver wrote:Hi, I have a TO-Q-SY2-JWT which has a shunt-resistor instead of the coil. Has anybody flashed such a device?
addChangeHandler Voltage > 251 POWER OFF
max_mcu wrote:Hello community, I have the following problem: The relay is a bi stable relay. When the power is lost and then switched back on, the switch + LED is not on if the relay was switched on before the power failure. How can I determine after the power failure whether the relay is still on or off? Can this be fixed in the software?
przemsi_ele wrote:>>21556434 .
yes, you can extract the original calibration configuration, there is a post on this topic, but I always calibrate with a classic bulb, it is almost the true resistance, in my cases it is always satisfactory
At first, I didn’t realize that during this type of calibration, a power factor of 1 is assumed by simply using the measured power value as the product of voltage and current (U × I).
TL;DR: For DIY users flashing the Tongou TO-Q-SY1-JWT, the reliable path is UART on the BK7231N: use 3.3 V, RX1/TX1, and pulse CEN to enter boot. One expert summary from the thread says, "UART flashing method" is the recommended approach, especially after CloudCutter failures on firmware 1.0.18. [#20974510]
Why it matters: This FAQ turns a long mixed-success forum thread into a fast, citation-ready guide for flashing, configuring, calibrating, and safely using Tongou DIN-rail switch/meter devices.
| Method | Works on non-metering 1.0.2 | Works on metering 1.0.18 | Case opening needed | Reliability in thread |
|---|---|---|---|---|
| Tuya CloudCutter | Yes | Often no | No | Mixed |
| UART flashing | Yes | Yes | Usually yes | High |
Key insight: P24 and P26 drive a bistable relay through an H-bridge, so treating them like a normal single-pin relay causes wrong startup behavior, heat, or no state restoration. [#21188194]
LED_n, P15 = WifiLED_n, P17 = Btn, P24 = BridgeFWD, and P26 = BridgeREV, with startDriver BL0942 for metering. [#20663290]LED_n;1, P15 WifiLED_n;0, P17 Btn;1, P24 BridgeFWD;1, and P26 BridgeREV;1, with the command backlog startDriver BL0942; startDriver NTP. That setup gives LED control, button input, bistable relay pulses, and BL0942 metering on the BK7231N version. Earlier posts showed Rel and Rel_n, but later testing on this model confirmed the bridge mapping is the correct control method for the relay hardware. [#21118531]BridgeFWD and BridgeREV because the device drives a bistable relay through an H-bridge, not a standard hold-coil relay. "Bistable relay" is a latching relay that changes state with a short pulse, then stays there mechanically without continuous coil power. On this Tongou design, P24 and P26 go to the MD7620A driver inputs, so single-pin Rel logic can leave state tracking wrong or drive the hardware incorrectly. Users also linked wrong bridge handling to hot coils and bad reboot behavior. [#21487925]SetStartValue 1 0 did not fully work with the bridge driver in early builds. In testing, SetStartValue 1 1 restored ON correctly, and SetStartValue 1 -1 correctly remembered the last state, while SetStartValue 1 0 left OpenBeken thinking the channel was OFF without sending the bridge pulse. A workaround used two boot events: pulse ON at 1 second, then OFF at 2 seconds. That workaround toggles the relay if it was already OFF before reboot. [#20700999]dInput, yet the button still did not switch the relay. The user found Flag 41, labeled child lock, was checked by default. After clearing that flag in Configure General, the button started toggling the switch normally. [#21118531]voltage_ref 15990, current_ref 124380, power_ref 309.8, and energy_ref 2659, then applying them in the BL0942 configuration. Users also confirmed that if extraction is unavailable, calibration with a known load, such as a 60 W incandescent lamp, gives acceptable results. [#21193078]