diff --git a/pychron/spectrometer/base_magnet.py b/pychron/spectrometer/base_magnet.py
index 3638ac677..dcecafc45 100644
--- a/pychron/spectrometer/base_magnet.py
+++ b/pychron/spectrometer/base_magnet.py
@@ -20,7 +20,7 @@
 from math import pi
 
 from numpy import arange, sin
-from traits.api import Property, Float, Event, Instance
+from traits.api import Property, Float, Event, Instance, Bool
 
 from pychron.core.yaml import yload
 from pychron.paths import paths
@@ -52,6 +52,9 @@ class BaseMagnet(SpectrometerDevice, FieldMixin):
 
     _suppress_mass_update = False
 
+    use_beam_blank = Bool(False)
+    beam_blank_threshold = Float(0.5)
+
     # def __init__(self, *args, **kw):
     #     super(BaseMagnet, self).__init__(*args, **kw)
     #     self._lock = threading.Lock()
@@ -86,6 +89,14 @@ def finish_loading(self):
         # load af demag
         self._load_af_demag_configuration()
 
+    def load_beam_blank(self, config):
+        pd = "Protection"
+        self.use_beam_blank = self.config_get(
+            config, pd, "use_beam_blank", cast="boolean", default=False
+        )
+        self.beam_blank_threshold = self.config_get(
+            config, pd, "beam_blank_threshold", cast="float", default=0.1
+        )
     # ===============================================================================
     # mapping
     # ===============================================================================
diff --git a/pychron/spectrometer/base_spectrometer.py b/pychron/spectrometer/base_spectrometer.py
index 7f8cde262..daf0170e0 100644
--- a/pychron/spectrometer/base_spectrometer.py
+++ b/pychron/spectrometer/base_spectrometer.py
@@ -468,6 +468,8 @@ def load(self):
         p = get_spectrometer_config_path(name)
         config = self.get_configuration_writer(p)
 
+        self.magnet.load_beam_blank(config)
+
         return config
 
     def load_molecular_weights(self):
diff --git a/pychron/spectrometer/isotopx/magnet/ngx.py b/pychron/spectrometer/isotopx/magnet/ngx.py
index a1a32e22f..aa1dae8ae 100644
--- a/pychron/spectrometer/isotopx/magnet/ngx.py
+++ b/pychron/spectrometer/isotopx/magnet/ngx.py
@@ -20,13 +20,11 @@
 
 
 class NGXMagnet(IsotopxMagnet):
-    _protect_detector = False
-
     def read_dac(self):
         return self.read_mass()
 
     def set_dac(self, v, *args, **kw):
-        return self.set_mass(v, deflect=self.microcontroller.protect_detector)
+        return self.set_mass(v, **kw)
 
     @get_float()
     def read_mass(self):
@@ -50,12 +48,18 @@ def set_mass(self, v, delay=None, deflect=False):
         self.microcontroller.stop_acquisition()
         # self.microcontroller.triggered = False
 
-        deflect = ",deflect" if deflect else ""
-        self.ask("SetMass {},{}{}".format(v, delay, deflect))
         dv = abs(self._dac - v)
         self._dac = v
-        change = dv > 1e-7
 
+        if self.use_beam_blank:
+            deflect = dv > self.beam_blank_threshold
+
+        self.debug(f'use beam blank={deflect}. dv={dv}, threshold={self.beam_blank_threshold}')
+
+        deflect = ",deflect" if deflect else ""
+        self.ask(f"SetMass {v},{delay}{deflect}")
+
+        change = dv > 1e-7
         return change
 
 
diff --git a/pychron/spectrometer/thermo/spectrometer/base.py b/pychron/spectrometer/thermo/spectrometer/base.py
index be1321806..755cee27b 100644
--- a/pychron/spectrometer/thermo/spectrometer/base.py
+++ b/pychron/spectrometer/thermo/spectrometer/base.py
@@ -337,15 +337,9 @@ def load(self):
 
         pd = "Protection"
         if config.has_section(pd):
-            self.magnet.use_beam_blank = self.config_get(
-                config, pd, "use_beam_blank", cast="boolean", default=False
-            )
             self.magnet.use_detector_protection = self.config_get(
                 config, pd, "use_detector_protection", cast="boolean", default=False
             )
-            self.magnet.beam_blank_threshold = self.config_get(
-                config, pd, "beam_blank_threshold", cast="float", default=0.1
-            )
 
             # self.magnet.detector_protection_threshold = self.config_get(config, pd,
             # 'detector_protection_threshold',
@@ -369,6 +363,8 @@ def load(self):
         for d in self.detectors:
             d.load_deflection_coefficients()
 
+        return config
+
     def start(self):
         self.debug(
             "********** Spectrometer start. send configuration: {}".format(