FAQ
TL;DR: Idle standby current sits at 8 – 12.5 mA—“device gets quiet hot” [Elektroda, rufus4, post #21024659]—yet three-wire flashing takes <2 min and success rate hits 100 % after a few attempts [Elektroda, max4elektroda, post #20965239]
Why it matters: Knowing the quirks avoids bricked plugs, overheats, and MQTT headaches.
Quick Facts
• PCB: BSD342-2110 (or BSD34-202110 variant) with LN882H Wi-Fi SiP + BL0937 meter [Elektroda, max4elektroda, post #20965239]
• Relay rating: printed "16 A / 20 A"; treat as 16 A continuous for safety [Elektroda, photo, post #20965239]
• Flash wiring: only VCC 3.3 V, RX0, TX0 needed; use mains pin as GND [Elektroda, 20965239]
• Power draw (OpenBK, relay OFF/ON): 8.5 mA / 12.5 mA ≈ 2–3 W [Elektroda, rufus4, post #21024659]
• Selling link: AliExpress “Digitaling Store”, item 1005005665258417 (availability may change) [Elektroda, 20965724]
How do I open the Elvico LSPA9 plug without breaking the case?
Squeeze the long sides in a vice padded with cardboard until the light glue joint cracks, then twist slightly; five units opened this way showed no damage [Elektroda, 20965239]
Which pins must I solder to flash OpenBeken firmware?
Solder only three: VCC 3.3 V, RX0, TX0. Clip the mains pin opposite the LN882H module for GND. Short boot-pin A9 to GND for a few seconds at power-up to enter flash mode [Elektroda, 20965239]
Quick 3-step flashing procedure?
- Connect VCC, RX0, TX0, and use mains pin as GND.
- Power plug, momentarily short A9 to GND; LED stays dark if timing is right.
- Run LN882H_CMD_Tool at 115 200 bps: download flash 0x0 firmware.bin. Retry every 5 s if needed.
[Elektroda, 20965239]
Why does firmware ≥1.17.513 reboot repeatedly?
Early builds hit watchdog resets when the Web-GUI loads; accessing only the Web-app or downgrading to ≤512 stops the loop [Elektroda, Raufaser, post #21015608] Firmware 1.17.530 and later resolved the issue for most users [Elektroda, 21034099]
My socket disappears from Wi-Fi after 48 h—fixes?
Update to OpenLN882H_1.17.530 or newer and issue Powersave 1 after boot; units then showed >168 h stable uptime [Elektroda, 21034099] Edge case: one user needed a full re-flash with vendor FW first [Elektroda, rufus4, post #21022643]
What is the correct button and relay pin mapping?
Default template maps A3 to Btn 0 and A11 to Rel 0. If the hardware variant uses another GPIO, locate it with Pin Doctor and update the template [Elektroda, 21022708]
Can I change the LED colours?
Yes. Set GPIO10 to LED for Tuya-style (blue OFF, red ON) or to WifiLED for activity-only; WifiLED_n lights purple because both diodes are active [Elektroda, #21067095; #21067385].
Recommended MQTT topics for ioBroker or Home Assistant?
OpenBeken publishes state to /0/get and accepts commands at /0/set. Creating cmnd/stat branches isn’t required. Home Assistant auto-discovers; ioBroker needs manual numeric writable state ‘set’. Button presses update the ‘get’ topic instantly [Elektroda, #21064461; #21064315].
What’s the real current limit of the relay?
Label shows 16 A on plastic and 20 A on metal can. Treat it as 16 A continuous (≈ 3.5 kW @ 230 V) to stay within IEC safety margins [Song Chuan datasheet] & [Elektroda, 20965239]
Does Powersave reduce heat?
Yes. CPU temperature drops from ~60 °C (Powersave 0) to ~40 °C (Powersave 1). Total draw remains ~8 mA idle, yet casing feels cooler [Elektroda, 21023618]
Where can I still buy the LN882H LSPA9 version?
Recent verified orders came from AliExpress ‘Digitaling Store’, item 1005005665258417; supply can change without notice [Elektroda, #20965724; #21004486].
Any dumped original firmware available?
A complete binary backup was posted for community use [Elektroda, Raufaser, post #21004486] Keep it to restore Tuya firmware if needed.
Edge case: What if the push-button feels unresponsive?
Several BSD34-202110 boards shipped with stiff tact switches; extra pressure needed. Replace the 4-pin SMD switch or add a parallel through-hole tact for reliable clicks [Elektroda, rufus4, post #21022878]
Statistic: How does LSPA9 idle power compare to Shelly Plug?
At 2–3 W idle, LSPA9 consumes roughly double a Shelly Plug’s ~1 W standby, so bulk usage raises energy bills by about €1 year each per socket (0.30 €/kWh) [Elektroda, 21024659]
Is DHT sensor support working?
Not yet; OpenBeken on LN882H lacks stable DHT driver as of build 1.17.530. Expect future commits to enable it [Elektroda, rufus4, post #21034099]
