Troubleshooting Resources, Tools, and Equipment
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Figure 3-6. SDN Downstream Connector Gray
Ground Check
Procedure
The maximum ground potential difference between the third wire ground
delivered to an ACC and the third wire ground delivered to any of its SDN
instruments, with the SDN cables disconnected, is 500 mV RMS.
The following check will usually indicate if a grounding problem exists on
a given branch without taking the whole system down.
a. At the end of the branch cable in question turn off and unplug the
instruments using that branch.
b. Measure the voltage between the ground coming through the SDN wall
box and the third wire ground of each instrument’s wall outlet. The
value measured on an voltmeter must not exceed 500 mV RMS.
78534A Monitor/Terminal
Downstream Connector (gray)
Pin B (–)
Priority Wire—Black
(negative)
Pin C (+)
Priority Wire—Gray
(positive)
Pin A (+)
Data Wire—Pink
(positive)
Pin E (–)
Data Wire—Blue
(negative)
Pin D (GND)
Drain Wires—Ground
Summary of Contents for 78581B
Page 46: ...ACC Maintenance 4 2 ...
Page 54: ...Installation Responsibilities Customer and Agilent Technologies 6 4 ...
Page 90: ...Procedures 8 28 ...
Page 98: ...Contacts 10 6 ...
