Set up the hubs to auto-calibrate voltage to a target automatically on first startup to alleviate the need for manual calibration.

currentmonitor/lantern-currentmonitor/src/main/java/com/lanternsoftware/currentmonitor/CurrentMonitor.java

@@ -62,6 +62,39 @@ public class CurrentMonitor {
 		debug = _debug;
 	}
 
+	public double calibrateVoltage(double _curCalibration, float _voltage) {
+		GpioPinAnalogInput voltagePin = getPin(0, 0);
+		if (voltagePin == null)
+			return 0.0;
+		List<Double> samples = new ArrayList<>(120000);
+		long intervalEnd = System.nanoTime() + 2000000000L; //Scan voltage for 2 seconds
+		while (System.nanoTime() < intervalEnd) {
+			samples.add(voltagePin.getValue());
+		}
+
+		double vOffset = 0.0;
+		for (Double sample : samples) {
+			vOffset += sample;
+		}
+		vOffset /= samples.size();
+		double vRms = 0.0;
+		for (Double sample : samples) {
+			sample -= vOffset;
+			vRms += sample * sample;
+		}
+		vRms /= samples.size();
+		double oldVrms = _curCalibration * Math.sqrt(vRms);
+		if (oldVrms < 20) {
+			LOG.info("Could not get a valid voltage read, please check that your AC/AC transformer is connected");
+			return 0.0;
+		}
+		double newCal = (_voltage/oldVrms) * _curCalibration;
+		double newVrms = newCal * Math.sqrt(vRms);
+		LOG.info("Old Voltage Calibration: {}  Old vRMS: {}", _curCalibration, oldVrms);
+		LOG.info("New Voltage Calibration: {}  New vRMS: {}", newCal, newVrms);
+		return newCal;
+	}
+
 	public void monitorPower(BreakerHub _hub, List<Breaker> _breakers, int _intervalMs, PowerListener _listener) {
 		stopMonitoring();
 		listener = _listener;

currentmonitor/lantern-currentmonitor/src/main/java/com/lanternsoftware/currentmonitor/MonitorApp.java

@@ -179,9 +179,17 @@ public class MonitorApp {
 			ConcurrencyUtils.sleep(5000);
 		}
 		LOG.info("Breaker Config loaded");
-		LOG.debug(DaoSerializer.toJson(breakerConfig));
 		BreakerHub hub = breakerConfig.getHub(config.getHub());
 		if (hub != null) {
+			if (config.isNeedsCalibration() && (config.getAutoCalibrationVoltage() != 0.0)) {
+				double newCal = monitor.calibrateVoltage(hub.getVoltageCalibrationFactor(), config.getAutoCalibrationVoltage());
+				if (newCal != 0.0) {
+					hub.setVoltageCalibrationFactor(newCal);
+					config.setNeedsCalibration(false);
+					ResourceLoader.writeFile(WORKING_DIR + "config.json", DaoSerializer.toJson(config));
+					post(DaoSerializer.toZipBson(breakerConfig), "currentmonitor/config");
+				}
+			}
 			List<Breaker> breakers = breakerConfig.getBreakersForHub(config.getHub());
 			LOG.info("Monitoring {} breakers for hub {}", CollectionUtils.size(breakers), hub.getHub());
 			monitor.monitorPower(hub, breakers, 1000, logger);

currentmonitor/lantern-currentmonitor/src/main/java/com/lanternsoftware/currentmonitor/MonitorConfig.java

@@ -14,6 +14,8 @@ public class MonitorConfig {
 	private int connectTimeout;
 	private int socketTimeout;
 	private int updateInterval;
+	private float autoCalibrationVoltage;
+	private boolean needsCalibration;
 
 	public MonitorConfig() {
 	}
@@ -94,4 +96,20 @@ public class MonitorConfig {
 	public void setUpdateInterval(int _updateInterval) {
 		updateInterval = _updateInterval;
 	}
+
+	public float getAutoCalibrationVoltage() {
+		return autoCalibrationVoltage;
+	}
+
+	public void setAutoCalibrationVoltage(float _autoCalibrationVoltage) {
+		autoCalibrationVoltage = _autoCalibrationVoltage;
+	}
+
+	public boolean isNeedsCalibration() {
+		return needsCalibration;
+	}
+
+	public void setNeedsCalibration(boolean _needsCalibration) {
+		needsCalibration = _needsCalibration;
+	}
 }

currentmonitor/lantern-currentmonitor/src/main/java/com/lanternsoftware/currentmonitor/dao/MonitorConfigSerializer.java

@@ -5,7 +5,6 @@ import com.lanternsoftware.util.dao.AbstractDaoSerializer;
 import com.lanternsoftware.util.dao.DaoEntity;
 import com.lanternsoftware.util.dao.DaoProxyType;
 import com.lanternsoftware.util.dao.DaoSerializer;
-
 import java.util.Collections;
 import java.util.List;
 
@@ -32,9 +31,11 @@ public class MonitorConfigSerializer extends AbstractDaoSerializer<MonitorConfig
 		d.put("password", _o.getPassword());
 		d.put("hub", _o.getHub());
 		d.put("debug", _o.isDebug());
-		d.put("socket_timeout", _o.getSocketTimeout());
 		d.put("connect_timeout", _o.getConnectTimeout());
+		d.put("socket_timeout", _o.getSocketTimeout());
 		d.put("update_interval", _o.getUpdateInterval());
+		d.put("auto_calibration_voltage", _o.getAutoCalibrationVoltage());
+		d.put("needs_calibration", _o.isNeedsCalibration());
 		return d;
 	}
 
@@ -48,9 +49,11 @@ public class MonitorConfigSerializer extends AbstractDaoSerializer<MonitorConfig
 		o.setPassword(DaoSerializer.getString(_d, "password"));
 		o.setHub(DaoSerializer.getInteger(_d, "hub"));
 		o.setDebug(DaoSerializer.getBoolean(_d, "debug"));
-		o.setSocketTimeout(DaoSerializer.getInteger(_d, "socket_timeout"));
 		o.setConnectTimeout(DaoSerializer.getInteger(_d, "connect_timeout"));
+		o.setSocketTimeout(DaoSerializer.getInteger(_d, "socket_timeout"));
 		o.setUpdateInterval(DaoSerializer.getInteger(_d, "update_interval"));
+		o.setAutoCalibrationVoltage(DaoSerializer.getFloat(_d, "auto_calibration_voltage"));
+		o.setNeedsCalibration(DaoSerializer.getBoolean(_d, "needs_calibration"));
 		return o;
 	}
 }