Update Legrand 412170: add note about device_mode auto producing erratic behavior (#5102)

Author: alexhk

docs/devices/412170.md

@@ -25,6 +25,10 @@ pageClass: device-page
 
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+## Notes
+
+The factory-default device_mode produces erratic relay behavior with the L to C1 push-button wiring shown in Legrand's wiring instructions. Set device_mode to switch for predictable operation. The auto value appears to be a leftover from cloning the 412171 contactor entry: this 412170 has no corresponding "Off-peak/peak time" (auto) setting in the official Legrand Home+Control app (unlike the 412171, which does).
+
 
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