diff --git a/frappy/lib/__init__.py b/frappy/lib/__init__.py
index 79c7fa5f..b227c13c 100644
--- a/frappy/lib/__init__.py
+++ b/frappy/lib/__init__.py
@@ -492,15 +492,3 @@ def delayed_import(modname):
     except Exception:
         return _Raiser(modname)
     return module
-
-
-class LazyImport:
-    module = None
-
-    def __init__(self, modulename):
-        self.modulename = modulename
-
-    def __getattr__(self, name):
-        if self.module is None:
-            self.module = __import__(self.modulename)
-        return getattr(self.module, name)
\ No newline at end of file
diff --git a/frappy_psi/lakeshore.py b/frappy_psi/lakeshore.py
index 5db8fe44..24d8b4c7 100644
--- a/frappy_psi/lakeshore.py
+++ b/frappy_psi/lakeshore.py
@@ -22,6 +22,8 @@ import time
 import math
 import random
 import threading
+import numpy as np
+from numpy.testing import assert_approx_equal
 
 from frappy.core import Module, Readable, Parameter, Property, \
     HasIO, StringIO, Writable, IDLE, ERROR, BUSY, DISABLED, nopoll, Attached
@@ -30,15 +32,12 @@ from frappy.datatypes import IntRange, FloatRange, StringType, \
 from frappy.errors import CommunicationFailedError, ConfigError, \
     HardwareError, DisabledError, ImpossibleError, secop_error, SECoPError
 from frappy.lib.units import NumberWithUnit, format_with_unit
-from frappy.lib import formatStatusBits, LazyImport
+from frappy.lib import formatStatusBits
+from frappy_psi.calcurve import CalCurve
 from frappy_psi.convergence import HasConvergence
 from frappy.mixins import HasOutputModule, HasControlledBy
 from frappy.extparams import StructParam
 
-np = LazyImport('numpy')
-np_testing = LazyImport('numpy.testing')
-calcurve_module = LazyImport('frappy_psi.calcurve')
-
 
 def string_to_num(string):
     try:
@@ -420,7 +419,7 @@ class Device(HasLscIO, Module):
         """check whether a returned calibration point is equal within curve point precision"""
         for v1, v2, eps in zip(left, right, fixeps):
             try:
-                np_testing.assert_approx_equal(v1, v2, significant, verbose=False)
+                assert_approx_equal(v1, v2, significant, verbose=False)
             except AssertionError:
                 return abs(v1 - v2) < eps
         return True
@@ -465,7 +464,7 @@ class CurveRequest:
         self.action = device.find_curve
         self.new_sensors = set()
         self.sensors = {sensor.channel: sensor}
-        calcurve = calcurve_module.CalCurve(sensor.calcurve)
+        calcurve = CalCurve(sensor.calcurve)
         equipment_id = device.propertyValues.get('original_id') or device.secNode.equipment_id
         name = f"{equipment_id.split('.')[0]}.{sensor.name}"
         sn = calcurve.calibname
@@ -613,16 +612,19 @@ class Sensor(Base, Readable):
 
     @nopoll
     def read_value(self):
-        self.status, value, self.raw = self.get_data()
+        self.status, value, raw = self.get_data()
         if isinstance(value, SECoPError):
-            raise value.copy()
+            raise value
+        if not isinstance(raw, SECoPError):
+            self.raw = raw
         return value
 
     @nopoll
     def read_raw(self):
-        self.status, self.value, raw = self.get_data()
+        self.status, value, raw = self.get_data()
         if isinstance(raw, SECoPError):
-            raise raw.copy()
+            raise raw
+        self.value = value
         return raw
 
     def read_status(self):