A part of the signal processing circuit connected to the probe is isolated by {HEAD ~ an isolation circuit} to secure {TAIL ~ the safety} 
to secure
A part of the signal processing circuit connected to the probe is isolated by { HEAD ~ an isolation circuit } to secure { TAIL ~ the safety }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL