Index: CN0_Python_Scripts/data_analysis.py
===================================================================
diff -u -rcf2d4ebc110a148e31ce7a7ee049691b101abe21 -re5e6c6f79e38c2f82de516ea81069dfe0fc558b5
--- CN0_Python_Scripts/data_analysis.py	(.../data_analysis.py)	(revision cf2d4ebc110a148e31ce7a7ee049691b101abe21)
+++ CN0_Python_Scripts/data_analysis.py	(.../data_analysis.py)	(revision e5e6c6f79e38c2f82de516ea81069dfe0fc558b5)
@@ -3,8 +3,14 @@
 from datetime import datetime
 import atexit
 from openpyxl import Workbook, load_workbook
+import os
 
-EXCEL_PATH = "autopoll_log.xlsx"
+# === 1) Create a run-specific timestamp and filename ===
+RUN_TS = datetime.now().strftime("%Y%m%d-%H%M%S")  # e.g., 20260224-112905
+# Optional: choose an output directory (create it if needed)
+EXCEL_DIR = "."  # change to e.g., "logs" if desired
+os.makedirs(EXCEL_DIR, exist_ok=True)
+EXCEL_PATH = os.path.join(EXCEL_DIR, f"autopoll_log_{RUN_TS}.xlsx")
 
 # Keep workbook open for performance
 _wb = None
@@ -13,8 +19,8 @@
 
 # Per-sheet headers (include units in the Value column)
 HEADER_MAP = {
-    "Resistance": ["Number", "Date", "Time", "Value (Ohms)", "Read Count", "Error"],
-    "Temperature":  ["Number", "Date", "Time", "Value (°C)", "Read Count", "Error"],
+    "Conductivity": ["Number", "Date", "Time", "Resistance (Ohms)", "Read Count", "Error"],
+    "Temperature":  ["Number", "Date", "Time", "Resistance (Ohms)", "Read Count", "Error"],
 }
 
 ########################################################################################################################
@@ -62,7 +68,7 @@
         return ws
 
     # Ensure both sheets with their respective headers
-    _ws_map["Resistance"] = ensure_sheet("Resistance", HEADER_MAP["Resistance"])
+    _ws_map["Conductivity"] = ensure_sheet("Conductivity", HEADER_MAP["Conductivity"])
     _ws_map["Temperature"]  = ensure_sheet("Temperature",  HEADER_MAP["Temperature"])
 
     # Remove default "Sheet" if unused and not one of our targets
@@ -92,10 +98,13 @@
 
 
 def log_to_excel(kind: str, ts: datetime, value: float, read_count: int, error: int, path: str = EXCEL_PATH):
+
+    path = EXCEL_PATH
+
     """
     Append a row to the Excel workbook.
 
-    kind: "Resistance" or "Temperature"
+    kind: "Conductivity" or "Temperature"
     ts: datetime timestamp
     value: float
     read_count: int