diff --git a/src/nodeClass.js b/src/nodeClass.js
index 2961de3..a40009f 100644
--- a/src/nodeClass.js
+++ b/src/nodeClass.js
@@ -11,6 +11,10 @@ class nodeClass extends BaseNodeAdapter {
   static commands = commands;
   static tickInterval = null;
   static statusInterval = 1000;
+  // Realized control position holds constant in steady state, so delta
+  // compression would emit it ~once and the Grafana "% Control" line goes
+  // invisible. Force it every tick so the pump's movement always traces.
+  static alwaysEmitFields = ['ctrl'];
 
   buildDomainConfig(uiConfig) {
     _rejectLegacyAssetFields(uiConfig);