diff --git a/pyproject.toml b/pyproject.toml
index b098173f..97e5f0c1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,7 +10,7 @@ dependencies = [
     "httpx>=0.27.2",
     "numpy>=1.9.0",
     "pandas>=2.2.3",
-    "pandera>=0.20.4",
+    "pandera==0.20.4", # https://github.com/unionai-oss/pandera/issues/1856
     "polyfactory>=2.17.0",
     "pydantic>=2.9.2",
     "rdflib>=7.0.0",
diff --git a/src/cimsparql/data_models.py b/src/cimsparql/data_models.py
index 65029e9f..d9e4bc6b 100644
--- a/src/cimsparql/data_models.py
+++ b/src/cimsparql/data_models.py
@@ -2,15 +2,16 @@
 from typing import Self
 
 import pandera as pa
+from pandera.api.pandas.model_config import BaseConfig
 from pandera.typing import DataFrame, Index, Series
 
 
-class JsonSchemaOut(pa.DataFrameModel):
-    class Config:
+class CoercingSchema(pa.DataFrameModel):
+    class Config(BaseConfig):
         coerce = True
 
 
-class FullModelSchema(JsonSchemaOut):
+class FullModelSchema(CoercingSchema):
     model: Series[str]
     time: Series[str]
     profile: Series[str]
@@ -25,7 +26,7 @@ def unique_time(cls, df: DataFrame[Self]) -> bool:
 FullModelDataFrame = DataFrame[FullModelSchema]
 
 
-class MridResourceSchema(JsonSchemaOut):
+class MridResourceSchema(CoercingSchema):
     """
     Common class for resources with an mrid as index
     """
@@ -56,7 +57,7 @@ class MarketDatesSchema(NamedResourceSchema):
 MarketDatesDataFrame = DataFrame[MarketDatesSchema]
 
 
-class BusDataSchema(JsonSchemaOut):
+class BusDataSchema(CoercingSchema):
     node: Index[str] = pa.Field(unique=True)
     busname: Series[str] = pa.Field()
     substation: Series[str] = pa.Field()
@@ -142,7 +143,7 @@ class ExchangeSchema(NamedMarketResourceSchema):
 ExchangeDataFrame = DataFrame[ExchangeSchema]
 
 
-class PhaseTapChangerSchema(JsonSchemaOut):
+class PhaseTapChangerSchema(CoercingSchema):
     mrid: Series[str] = pa.Field()
     phase_shift_increment: Series[float] = pa.Field()
     enabled: bool = pa.Field()
@@ -186,7 +187,7 @@ class TransfConToConverterSchema(NamedResourceSchema):
 TransfConToConverterDataFrame = DataFrame[TransfConToConverterSchema]
 
 
-class CoordinatesSchema(JsonSchemaOut):
+class CoordinatesSchema(CoercingSchema):
     mrid: Series[str] = pa.Field()
     x: Series[float] = pa.Field()
     y: Series[float] = pa.Field()
@@ -230,7 +231,7 @@ class AcLinesSchema(ShuntComponentSchema):
 AcLinesDataFrame = DataFrame[AcLinesSchema]
 
 
-class TransformersSchema(JsonSchemaOut):
+class TransformersSchema(CoercingSchema):
     name: Series[str] = pa.Field()
     p_mrid: Series[str] = pa.Field()
     w_mrid: Series[str] = pa.Field()
@@ -253,7 +254,7 @@ class TransformerWindingSchema(ShuntComponentSchema):
 TransformerWindingDataFrame = DataFrame[TransformerWindingSchema]
 
 
-class SubstationVoltageSchema(JsonSchemaOut):
+class SubstationVoltageSchema(CoercingSchema):
     substation: Index[str] = pa.Field()
     container: Series[str] = pa.Field()
     v: Series[float] = pa.Field()
@@ -262,7 +263,7 @@ class SubstationVoltageSchema(JsonSchemaOut):
 SubstationVoltageDataFrame = DataFrame[SubstationVoltageSchema]
 
 
-class DisconnectedSchema(JsonSchemaOut):
+class DisconnectedSchema(CoercingSchema):
     mrid: Series[str] = pa.Field(unique=True)
 
 
@@ -305,7 +306,7 @@ class RegionsSchema(MridResourceSchema):
 RegionsDataFrame = DataFrame[RegionsSchema]
 
 
-class StationGroupCodeNameSchema(JsonSchemaOut):
+class StationGroupCodeNameSchema(CoercingSchema):
     station_group: Index[str] = pa.Field(unique=True)
     name: Series[str] = pa.Field()
     alias_name: Series[str] = pa.Field(nullable=True)
@@ -322,7 +323,7 @@ class HVDCBidzonesSchema(MridResourceSchema):
 HVDCBidzonesDataFrame = DataFrame[HVDCBidzonesSchema]
 
 
-class TransformerWindingsSchema(JsonSchemaOut):
+class TransformerWindingsSchema(CoercingSchema):
     mrid: Series[str] = pa.Field()
     end_number: Series[int] = pa.Field(gt=0)
     w_mrid: Index[str] = pa.Field(unique=True)
@@ -331,7 +332,7 @@ class TransformerWindingsSchema(JsonSchemaOut):
 TransformerWindingsDataFrame = DataFrame[TransformerWindingsSchema]
 
 
-class SvInjectionSchema(JsonSchemaOut):
+class SvInjectionSchema(CoercingSchema):
     node: Series[str] = pa.Field(unique=True)
     p: Series[float] = pa.Field()
     q: Series[float] = pa.Field()
@@ -340,7 +341,7 @@ class SvInjectionSchema(JsonSchemaOut):
 SvInjectionDataFrame = DataFrame[SvInjectionSchema]
 
 
-class RASEquipmentSchema(JsonSchemaOut):
+class RASEquipmentSchema(CoercingSchema):
     mrid: Series[str] = pa.Field(unique=True)
     equipment_mrid: Series[str] = pa.Field()
     name: Series[str] = pa.Field()
@@ -349,7 +350,7 @@ class RASEquipmentSchema(JsonSchemaOut):
 RASEquipmentDataFrame = DataFrame[RASEquipmentSchema]
 
 
-class Switches(JsonSchemaOut):
+class Switches(CoercingSchema):
     mrid: Index[str] = pa.Field(unique=True)
     is_open: Series[bool] = pa.Field()
     equipment_type: Series[str] = pa.Field()
@@ -360,7 +361,7 @@ class Switches(JsonSchemaOut):
 SwitchesDataFrame = DataFrame[Switches]
 
 
-class ConnectivityNode(JsonSchemaOut):
+class ConnectivityNode(CoercingSchema):
     mrid: Index[str] = pa.Field(unique=True)
     container: Series[str] = pa.Field()
     container_name: Series[str] = pa.Field()
@@ -373,7 +374,7 @@ class ConnectivityNode(JsonSchemaOut):
 ConnectivityNodeDataFrame = DataFrame[ConnectivityNode]
 
 
-class SvPowerDeviationSchema(JsonSchemaOut):
+class SvPowerDeviationSchema(CoercingSchema):
     node: Series[str] = pa.Field(unique=True)
     sum_terminal_flow: Series[float] = pa.Field()
     reported_sv_injection: Series[float] = pa.Field()
@@ -384,7 +385,7 @@ class SvPowerDeviationSchema(JsonSchemaOut):
 SvPowerDeviationDataFrame = DataFrame[SvPowerDeviationSchema]
 
 
-class HVDC(JsonSchemaOut):
+class HVDC(CoercingSchema):
     converter_mrid_1: Series[str] = pa.Field()
     converter_mrid_2: Series[str] = pa.Field()
     name: Series[str] = pa.Field()
@@ -394,7 +395,7 @@ class HVDC(JsonSchemaOut):
 HVDCDataFrame = DataFrame[HVDC]
 
 
-class BaseVoltage(JsonSchemaOut):
+class BaseVoltage(CoercingSchema):
     mrid: str = pa.Field(unique=True)
     un: float = pa.Field()
     operating_voltage: float = pa.Field()
@@ -403,7 +404,7 @@ class BaseVoltage(JsonSchemaOut):
 BaseVoltageDataFrame = DataFrame[BaseVoltage]
 
 
-class AssociatedSwitches(JsonSchemaOut):
+class AssociatedSwitches(CoercingSchema):
     mrid: str = pa.Field(unique=True)
     name: str
     switch_mrids: str
diff --git a/tests/test_type_mapper.py b/tests/test_type_mapper.py
index 8b312a49..0c13eed0 100644
--- a/tests/test_type_mapper.py
+++ b/tests/test_type_mapper.py
@@ -11,7 +11,7 @@
 from pandas.testing import assert_frame_equal
 
 from cimsparql import type_mapper
-from cimsparql.data_models import JsonSchemaOut
+from cimsparql.data_models import CoercingSchema
 from cimsparql.graphdb import RestApi
 from cimsparql.model import ServiceConfig
 
@@ -126,8 +126,8 @@ def test_have_cim_version(httpserver: HTTPServer, cim_version: int, have_cim_ver
     assert tm.have_cim_version(str(cim_version)) == have_cim_version
 
 
-class FloatSchema(JsonSchemaOut):
-    float_col: pa.typing.Series[float] = pa.Field(nullable=True)
+class FloatSchema(CoercingSchema):
+    float_col: float = pa.Field(nullable=True)
 
 
 @pytest.mark.parametrize(