diff --git a/pypcc/config/UNB2TR.yaml b/pypcc/config/UNB2TR.yaml
index f92373cc5ca7b50f9220a1ac33e3e9b6d078ca43..248ada764781f0a6d0ef47473685ee9d2ea70c1e 100644
--- a/pypcc/config/UNB2TR.yaml
+++ b/pypcc/config/UNB2TR.yaml
@@ -389,6 +389,15 @@ variables:
      dim: 2
      monitor: true
 
+   - name: [UNB2_POL_QSFP_N01_IOUT,UNB2_POL_QSFP_N23_IOUT]
+     driver: switch_PS
+     devreg:  [POL_QSFP0.IOUT,POL_QSFP1.IOUT]
+     width: 16
+     rw:  ro
+     dtype: double
+     scale: smbus_2bytes_to_float
+     dim: 2
+
    - name: UNB2_DC_DC_48V_12V_IOUT
      driver: switch_PS
 #     devreg:  [DC_DC.IOUT,0x2.0x8C,0x1.0x8C,0xF.0x8C,0xE.0x8C,0xD.0x8C]
@@ -413,6 +422,15 @@ variables:
      dim: 2
      monitor: true
 
+   - name: [UNB2_POL_QSFP_N01_TEMP,UNB2_POL_QSFP_N23_TEMP]
+     driver: switch_PS
+     devreg:  [POL_QSFP0.TEMP,POL_QSFP1.TEMP]
+     width: 16
+     rw:  ro
+     dtype: double
+     scale: smbus_2bytes_to_float
+     dim: 2
+
    - name: UNB2_DC_DC_48V_12V_TEMP 
      driver: switch_PS
 #     devreg:  DC_DC.TEMP
diff --git a/pypcc/opcuaserv/yamlreader.py b/pypcc/opcuaserv/yamlreader.py
index 5c9183bdbb2fa8e9c9ba4bf2857a128131bbf656..aaf29f340c8d3b6b09584df6c8af8cd43daa8ffc 100644
--- a/pypcc/opcuaserv/yamlreader.py
+++ b/pypcc/opcuaserv/yamlreader.py
@@ -3,6 +3,7 @@ import struct
 import time
 from pypcc.yamlconfig import *
 import logging
+import numpy as np
 from .smbus_float import *
 from pypcc.opcuaserv import convert_unit
 def bytes2int(bts):
@@ -165,7 +166,7 @@ class yamlreader(yamlconfig):
         #print(v.name,dim)
         varvalue2=0
         if   datatype in ['uint8','uint16','uint32','uint64']:  varvalue2=dim1*[0]
-        elif datatype=='double':    varvalue2=dim1*[0.0] 
+        elif datatype=='double':    varvalue2=dim1*[np.nan] 
         elif datatype=='boolean':  varvalue2=dim1*[False] 
         elif datatype=='string':   varvalue2=dim1*[""]
         if len(varvalue2)==1: varvalue2=varvalue2[0];