diff --git a/sensgw/protocols/prologix.py b/sensgw/protocols/prologix.py
index aae8378..e8d63f7 100644
--- a/sensgw/protocols/prologix.py
+++ b/sensgw/protocols/prologix.py
@@ -86,12 +86,20 @@ class PrologixEndpointLoop:
             return default_cmds + extra
         return default_cmds
 
+    def _drain_errors(self, inst: Any, maxn: int = 20) -> list[str]:
+        out: list[str] = []
+        for _ in range(maxn):
+            e = str(inst.ask(":SYST:ERR?")).strip()
+            if e.startswith("0,") or "No error" in e:
+                break
+            out.append(e)
+        return out
+
     def _init_device(
         self, gpib_addr: int, driver_key: str, meta: dict[str, Any]
     ) -> None:
         key = (driver_key or "").strip().lower()
 
-        # Only init if the configured driver is explicitly Keithley2000
         if key not in KEITHLEY_DRIVER_KEYS:
             self._initialized_addrs.add(gpib_addr)
             return
@@ -108,11 +116,15 @@ class PrologixEndpointLoop:
             inst.write(cmd)
             time.sleep(0.02)
 
-            # Read error after each command; stop early if something is wrong
             err = str(inst.ask(":SYST:ERR?")).strip()
-            if not err.startswith("0,") and "No error" not in err:
-                log.error(f"Keithley init failed at {cmd}: {err}")
-                break
+            if err.startswith("0,") or "No error" in err:
+                continue
+
+            log.error(f"Keithley init error at {cmd}: {err}")
+
+        errs = self._drain_errors(inst)
+        if errs:
+            log.warning(f"Keithley @ {gpib_addr} init error queue leftover: {errs}")
 
         self._initialized_addrs.add(gpib_addr)
 
@@ -122,6 +134,7 @@ class PrologixEndpointLoop:
 
             res = self.endpoint.conn["resource"]
             to_ms = int(self.endpoint.conn.get("gpib_read_timeout_ms", 500))
+            log.info(f"gpib_read_timeout_ms set to {to_ms}")
 
             # auto=False gives us manual control over addressing
             self._adapter = PrologixAdapter(res, gpib_read_timeout=to_ms, auto=False)
@@ -208,7 +221,7 @@ class PrologixEndpointLoop:
                         )
                     except Exception as e:
                         log.error(
-                            f"Prologix error {b.device.device_key}/{b.channel.metric}: {e}"
+                            f"Prologix error {b.device.device_key}/{b.channel.metric} query={b.query!r}: {e}"
                         )
                         await self.writer.write_error(
                             device_id=b.device.device_id, error=f"prologix: {e}"