diff --git a/debye_bec/devices/ionization_chambers/ionization_chamber.py b/debye_bec/devices/ionization_chambers/ionization_chamber.py
index 6c2b9e0..572dd9c 100644
--- a/debye_bec/devices/ionization_chambers/ionization_chamber.py
+++ b/debye_bec/devices/ionization_chambers/ionization_chamber.py
@@ -1,4 +1,6 @@
-from typing import Literal
+from __future__ import annotations
+
+from typing import Literal, TYPE_CHECKING
 
 import numpy as np
 from ophyd import Component as Cpt
@@ -15,6 +17,9 @@ from debye_bec.devices.ionization_chambers.ionization_chamber_enums import (
     AmplifierGain,
 )
 
+if TYPE_CHECKING: #pragma: no cover
+    from bec_lib.devicemanager import ScanInfo
+
 
 class EpicsSignalSplit(EpicsSignal):
     """Wrapper around EpicsSignal with different read and write pv"""
@@ -44,21 +49,22 @@ class GasMixSetupControl(Device):
     gas2 = Cpt(EpicsSignalRO, suffix="Gas2", kind="config", doc="Gas 2")
     conc2 = Cpt(EpicsSignalRO, suffix="Conc2", kind="config", doc="Concentration 2")
     press = Cpt(EpicsSignalRO, suffix="PressTransm", kind="config", doc="Current Pressure")
-    status_msg = Cpt(EpicsSignalRO, suffix="StatusMsg0", kind="config", doc="Status")
 
 
 class HighVoltageSuppliesControl(Device):
     """HighVoltage Supplies Control for Ionization Chamber 0"""
 
-    hv_v = Cpt(EpicsSignalSplit, suffix="HV1-V", kind="config", doc="HV voltage")
-    hv_i = Cpt(EpicsSignalSplit, suffix="HV1-I", kind="config", doc="HV current")
-    grid_v = Cpt(EpicsSignalSplit, suffix="HV2-V", kind="config", doc="Grid voltage")
-    grid_i = Cpt(EpicsSignalSplit, suffix="HV2-I", kind="config", doc="Grid current")
+    hv_v = Cpt(EpicsSignalSplit, suffix="HV2-V", kind="config", doc="HV voltage")
+    hv_i = Cpt(EpicsSignalSplit, suffix="HV2-I", kind="config", doc="HV current")
+    grid_v = Cpt(EpicsSignalSplit, suffix="HV1-V", kind="config", doc="Grid voltage")
+    grid_i = Cpt(EpicsSignalSplit, suffix="HV1-I", kind="config", doc="Grid current")
 
 
 class IonizationChamber0(PSIDeviceBase):
     """Ionization Chamber 0, prefix should be 'X01DA-'."""
 
+    USER_ACCESS = ['set_gain', 'set_filter', 'set_hv', 'set_grid', 'fill']
+
     num = 1
     amp_signals = {
         "cOnOff": (
@@ -79,6 +85,9 @@ class IonizationChamber0(PSIDeviceBase):
     }
     amp = Dcpt(amp_signals)
     gmes = Cpt(GasMixSetupControl, suffix=f"ES-GMES:IC{num-1}")
+    gmes_status = Cpt(
+        EpicsSignalRO, suffix="ES-GMES:StatusMsg0", kind="config", doc='Status'
+    )
     hv = Cpt(HighVoltageSuppliesControl, suffix=f"ES1-IC{num-1}:")
     hv_en_signals = {
         "ext_ena": (
@@ -86,13 +95,13 @@ class IonizationChamber0(PSIDeviceBase):
             "ES1-IC0:HV-Ext-Ena",
             {"kind": "config", "doc": "External enable signal of HV"},
         ),
-        "ena": (EpicsSignalRO, "ES1-IC0:HV-Ena", {"kind": "config", "doc": "Enable signal of HV"}),
+        "ena": (EpicsSignal, "ES1-IC0:HV-Ena", {"kind": "config", "doc": "Enable signal of HV"}),
     }
     hv_en = Dcpt(hv_en_signals)
 
-    def __init__(self, name: str, scan_info=None, **kwargs):
+    def __init__(self, name: str, prefix: str = "", scan_info: ScanInfo | None = None, **kwargs):
         self.timeout_for_pvwait = 2.5
-        super().__init__(name=name, scan_info=scan_info, **kwargs)
+        super().__init__(name=name, prefix=prefix, scan_info=scan_info, **kwargs)
 
     @typechecked
     def set_gain(self, gain: Literal["1e6", "1e7", "5e7", "1e8", "1e9"] | AmplifierGain) -> None:
@@ -180,9 +189,9 @@ class IonizationChamber0(PSIDeviceBase):
             hv (float) : Desired voltage for the 'HV' terminal. Voltage has to be between 0...3000
         """
 
-        if not 0 < hv < 3000:
+        if not 0 <= hv <= 3000:
             raise ValueError(f"specified HV {hv} not within range [0 .. 3000]")
-        if self.hv.grid_v.get() > hv:
+        if not np.isclose(np.abs(hv - self.hv.grid_v.get()), 0,  atol=3):
             raise ValueError(f"Grid {self.hv.grid_v.get()} must not be higher than HV {hv}!")
 
         if not self.hv_en.ena.get() == 1:
@@ -208,9 +217,9 @@ class IonizationChamber0(PSIDeviceBase):
             grid (float) : Desired voltage for the 'Grid' terminal, Grid Voltage has to be between 0...3000
         """
 
-        if not 0 < grid < 3000:
+        if not 0 <= grid <= 3000:
             raise ValueError(f"specified Grid {grid} not within range [0 .. 3000]")
-        if grid > self.hv.hv_v.get():
+        if not np.isclose(np.abs(grid - self.hv.hv_v.get()), 0,  atol=3):
             raise ValueError(f"Grid {grid} must not be higher than HV {self.hv.hv_v.get()}!")
 
         if not self.hv_en.ena.get() == 1:
@@ -271,7 +280,7 @@ class IonizationChamber0(PSIDeviceBase):
         timeout = 3
         if not self.wait_for_condition(wait_for_status, timeout=timeout, check_stopped=True):
             raise TimeoutError(
-                f"Ionization chamber filling process did not start after {timeout}s. Last log message {self.gmes.status_msg.get()}"
+                f"Ionization chamber filling process did not start after {timeout}s. Last log message {self.gmes_status.get()}"
             )
 
         def wait_for_filling_finished():
@@ -286,8 +295,8 @@ class IonizationChamber0(PSIDeviceBase):
         return status
 
 
-class IonizationChamber1(PSIDeviceBase):
-    """Ionization Chamber 0, prefix should be 'X01DA-'."""
+class IonizationChamber1(IonizationChamber0):
+    """Ionization Chamber 1, prefix should be 'X01DA-'."""
 
     num = 2
     amp_signals = {
@@ -309,6 +318,9 @@ class IonizationChamber1(PSIDeviceBase):
     }
     amp = Dcpt(amp_signals)
     gmes = Cpt(GasMixSetupControl, suffix=f"ES-GMES:IC{num-1}")
+    gmes_status = Cpt(
+        EpicsSignalRO, suffix="ES-GMES:StatusMsg0", kind="config", doc='Status'
+    )
     hv = Cpt(HighVoltageSuppliesControl, suffix=f"ES2-IC{num-1}:")
     hv_en_signals = {
         "ext_ena": (
@@ -316,13 +328,13 @@ class IonizationChamber1(PSIDeviceBase):
             "ES2-IC12:HV-Ext-Ena",
             {"kind": "config", "doc": "External enable signal of HV"},
         ),
-        "ena": (EpicsSignalRO, "ES2-IC12:HV-Ena", {"kind": "config", "doc": "Enable signal of HV"}),
+        "ena": (EpicsSignal, "ES2-IC12:HV-Ena", {"kind": "config", "doc": "Enable signal of HV"}),
     }
     hv_en = Dcpt(hv_en_signals)
 
 
-class IonizationChamber2(PSIDeviceBase):
-    """Ionization Chamber 0, prefix should be 'X01DA-'."""
+class IonizationChamber2(IonizationChamber0):
+    """Ionization Chamber 2, prefix should be 'X01DA-'."""
 
     num = 3
     amp_signals = {
@@ -344,6 +356,9 @@ class IonizationChamber2(PSIDeviceBase):
     }
     amp = Dcpt(amp_signals)
     gmes = Cpt(GasMixSetupControl, suffix=f"ES-GMES:IC{num-1}")
+    gmes_status = Cpt(
+        EpicsSignalRO, suffix="ES-GMES:StatusMsg0", kind="config", doc='Status'
+    )
     hv = Cpt(HighVoltageSuppliesControl, suffix=f"ES2-IC{num-1}:")
     hv_en_signals = {
         "ext_ena": (
@@ -351,6 +366,6 @@ class IonizationChamber2(PSIDeviceBase):
             "ES2-IC12:HV-Ext-Ena",
             {"kind": "config", "doc": "External enable signal of HV"},
         ),
-        "ena": (EpicsSignalRO, "ES2-IC12:HV-Ena", {"kind": "config", "doc": "Enable signal of HV"}),
+        "ena": (EpicsSignal, "ES2-IC12:HV-Ena", {"kind": "config", "doc": "Enable signal of HV"}),
     }
     hv_en = Dcpt(hv_en_signals)