diff --git a/custom_components/solax_modbus/plugin_growatt.py b/custom_components/solax_modbus/plugin_growatt.py
index dae70c92..92a1b0b3 100644
--- a/custom_components/solax_modbus/plugin_growatt.py
+++ b/custom_components/solax_modbus/plugin_growatt.py
@@ -2846,7 +2846,7 @@ def value_function_inverter_module(initval, descr, datadict):
         state_class = SensorStateClass.MEASUREMENT,
         register = 35,
         register_type = REG_INPUT,
-        unit = REGISTER_U32,
+        unit = REGISTER_S32,
         scale = 0.1,
         rounding = 1,
         allowedtypes = GEN2 | GEN3 | GEN4,