diff --git a/charge-controller-supervisor/src/tristar.rs b/charge-controller-supervisor/src/tristar.rs
index d5df060..5cdf5d1 100644
--- a/charge-controller-supervisor/src/tristar.rs
+++ b/charge-controller-supervisor/src/tristar.rs
@@ -55,9 +55,9 @@ pub struct Tristar {
     scaling: Option<Scaling>,
 }
 
-#[derive(Default, Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy)]
 pub struct TristarState {
-    scaling: Option<Scaling>,
+    scaling: Scaling,
     battery_voltage: f64,
     target_voltage: f64,
     input_current: f64,
@@ -86,7 +86,7 @@ impl TristarState {
     fn from_ram(ram: &[u16]) -> Self {
         let scaling = Scaling::from(ram);
         Self {
-            scaling: Some(scaling),
+            scaling,
             battery_voltage: scaling.get_voltage(ram[TristarRamAddress::AdcVbFMed]),
             target_voltage: scaling.get_voltage(ram[TristarRamAddress::VbRef]),
             input_current: scaling.get_current(ram[TristarRamAddress::AdcIaFShadow]),
@@ -266,6 +266,7 @@ impl Tristar {
                 let modbus_serial = tokio_serial::SerialStream::open(
                     &tokio_serial::new(port, *baud_rate).timeout(std::time::Duration::from_secs(3)),
                 )?;
+
                 tokio_modbus::client::rtu::attach_slave(modbus_serial, slave)
             }
             crate::config::Transport::Tcp { ip, port } => {
@@ -287,7 +288,7 @@ impl Tristar {
     pub async fn refresh(&mut self) -> eyre::Result<crate::controller::CommonData> {
         let new_state = self.get_data().await?;
 
-        self.scaling = new_state.scaling;
+        self.scaling = Some(new_state.scaling);
         self.consecutive_errors = 0;
         BATTERY_VOLTAGE
             .with_label_values(&[&self.friendly_name])