diff --git a/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs b/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs
index 8099b2cc5..dd827340c 100644
--- a/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs
+++ b/TestBenchFramework/BenchControl/TestMethods/iPerlCommunication/iPerlCommunicationForm.cs
@@ -1106,6 +1106,62 @@ namespace TBF.BenchControl.TestMethods.iPerlCommunication
 		}
 
 
+		/// <summary>
+		/// Write the calculated 2Hz correction factor to the memory.
+		/// </summary>
+		/// <param name="wm">Water meter object</param>
+		/// <param name="resultStr">String passed to caller</param>
+		/// <returns>true on success</returns>
+		static CommErr Write2HzCorrection(WaterMeters.iPerl.WaterMeter wm, ref string resultStr)
+		{
+			if (wm.CommFailed) return CommErr.CommFailed;
+
+			/// Write Q2 corrections
+			double hz2CorrectionFactor = wm.Hz2CorrectionFactor();
+			if (hz2CorrectionFactor == 0)
+			{
+				resultStr = string.Format("2Hz factors = 0 (writing bypassed)");
+				return CommErr.None;
+			}
+
+			if (OpenPort(wm) != 0) return CommErr.OpenPort;	/// Open RFID port
+
+			CommErr error = CommErr.Write;
+
+			Byte hz2CorrectionByte = (byte)((int)Math.Round(hz2CorrectionFactor) & 0x000000FF);
+			byte[] wrData = new byte[1] { hz2CorrectionByte };
+			///
+			for (int j = 0; j < cfg.MaxCommRetries; j++)
+			{
+				if (0 == WriteRequestPort(wm, MessageID.MetrologyMemory, Hz2CorrFactorsAddr, 1, wrData, cfg.CommTimeout)) { error = CommErr.None; break; }
+			}
+
+			if (error == CommErr.None)
+			{
+				error = CommErr.Verify;
+
+				/// Read calibration
+				byte[] rdData = null;
+				for (int j = 0; j < cfg.MaxCommRetries; j++)
+				{
+					if ((0 == ReadRequestPort(wm, MessageID.MetrologyMemory, Hz2CorrFactorsAddr, 1, out rdData, cfg.CommTimeout)) &&
+						(rdData != null) && (rdData.Length == 2) && (rdData[0] == hz2CorrectionByte))
+					{
+						error = CommErr.None;
+						resultStr = string.Format("2Hz factor = {0}", (SByte)hz2CorrectionByte);
+						rfidDataLogger.Warn(wm.Name + ": " + resultStr);
+						wm.Current2HzCorrection = hz2CorrectionFactor;
+						break;
+					}
+				}
+			}
+
+			ClosePort(wm);   /// Close RFID port
+
+			return error;
+		}
+
+
         /// <summary>
         /// Called when communication with one watermeter is completed
         /// </summary>
diff --git a/TestBenchFramework/BenchControl/WaterMeters/iPerl/WaterMeter.cs b/TestBenchFramework/BenchControl/WaterMeters/iPerl/WaterMeter.cs
index ebafcdcc5..51d0b39ee 100644
--- a/TestBenchFramework/BenchControl/WaterMeters/iPerl/WaterMeter.cs
+++ b/TestBenchFramework/BenchControl/WaterMeters/iPerl/WaterMeter.cs
@@ -113,8 +113,9 @@ namespace TBF.BenchControl.WaterMeters.iPerl
 
         public double Q2ErrorWOCorrection;
         public bool Q2CorrectionDone;
-		public double CurrentQ2Correction; 
+		public double CurrentQ2Correction;
 
+		public double Current2HzCorrection; 
 
 		/// <summary> Result of the last test used to calculate Q2 correction factors, etc </summary>
 		public Results.Entities.MeterTestRslt LastTestResult;
@@ -219,6 +220,55 @@ namespace TBF.BenchControl.WaterMeters.iPerl
 			return corrFactor;
 		}
 
+
+		/// <summary>
+		/// 2 Hz correction factor calculated from two Q3 tests - done at 2Hz and at 8Hz.
+		/// This factors should be used only for DN32 and DN40 meters.
+		/// </summary>
+		/// <returns>2 Hz correction factor</returns>
+		public double Hz2CorrectionFactor()
+		{
+			Q2ErrorWOCorrection = LastTestResult.Error;
+
+			if (Math.Abs(LastTestResult.Error) <= 0.5)
+			{
+				Q2CorrectionDone = false;
+				return 0;      /// No Q2 correction if error < +/-0.5 %
+			}
+
+			double A = 16.0 / ScalingFactor();		 /// Raw units per ml: DN15=16, DN20=8, DN25=4, DN32=2, DN40=1
+			const double B = 8.0;					 /// Raw units per minute, 8
+			const double C = B * 60.0;				 /// Raw units per hour, 480
+			double D = C / A;						 /// ml correction per hour
+			double F = D / (NominalTestFlow * 10.0); /// Error corrected with 8 Raw Units per minute [%]
+			double G = F / B;						 /// Error corrected with 1 Raw Unit per minute [%]
+
+			double errLimitLo = LastTestResult.ErrLimLo() + LastTestResult.Uncertainty();
+			double errLimitHi = LastTestResult.ErrLimHi() - LastTestResult.Uncertainty();
+
+			if (LastTestResult.Error < errLimitLo) return 0;	/// No Q2 correction if error too large -> WM failed
+			if (LastTestResult.Error > errLimitHi) return 0;	/// No Q2 correction if error too large -> WM failed
+
+			double volumeMeterErrLimLo = LastTestResult.VolumeRef * (100.0 + errLimitLo) / 100.0;
+			double volumeMeterErrLimHi = LastTestResult.VolumeRef * (100.0 + errLimitHi) / 100.0;
+
+			double corrFactorHi = (-1) * (errLimitLo / G) * (LastTestResult.VolumeRef / volumeMeterErrLimLo);		/// > 0
+			double corrFactorLo = (-1) * (errLimitHi / G) * (LastTestResult.VolumeRef / volumeMeterErrLimHi);		/// < 0
+
+			double corrFactor = (-1) * (LastTestResult.Error / G) * (LastTestResult.VolumeRef / LastTestResult.VolumeMeter);
+			double origCalulatedCorrFactor = corrFactor;
+
+			log.WarnFormat("Q2 correction: {0}, corrFactor={4}, error={3}% [Lo={1}%, Hi={2}%]",
+							Name,
+							errLimitLo.ToString("F1"),
+							errLimitHi.ToString("F1"),
+							LastTestResult.Error.ToString("F2"),
+							corrFactor.ToString("F1"));
+
+			Q2CorrectionDone = true;
+			return corrFactor;
+		}
+
         /// <summary> Name set by the test, to be used as a part of the opto-data log file name </summary>
         public string TestName;