Eaton’s Crouse-Hinds Business
Cooper Crouse-Hinds Pte Ltd
No. 2 Serangoon North Ave 5 #06-01
Singapore 554911
tel: + 65 6645 9888
fax: +65 6297 4819
Page 40
The following conditions can occur on a segment block node:
Parameter
Symbol / Alert
Remedy
Segment
Voltage
Low Alert
Low PreAlert
High PreAlert
High Alert
Check fieldbus power supply operation
Average low
frequency
noise
High PreAlert
High Alert
Check:
1.
Fieldbus screen is correctly cut back and taped at each of the fieldbus
devices;
2.
Fieldbus screen connections are correctly made in fieldbus wiring block
junction box, intermediate junction boxes, in marshalling cabinet and
correctly connected to ground;
3.
No AC cabling close to fieldbus cabling;
4.
Wire terminations are properly secured.
Average in-
band
frequency
noise
(fieldbus
frequency)
High PreAlert
High Alert
Check:
1.
Fieldbus screen is correctly cut back and taped at each of the fieldbus
devices;
2.
Fieldbus screen connections are correctly made in fieldbus wiring block
junction box, intermediate junction boxes, in marshalling cabinet and
correctly connected to ground;
3.
No AC cabling close to fieldbus cabling;
4.
Wire terminations are properly secured;
5.
For welding in the plant;
6.
Poor grounding of frequency controlled drives;
7.
Use of high power radios close to fieldbus network.
Average
high
frequency
noise
High PreAlert
High Alert
Check:
1.
For welding in the plant;
2.
Poor grounding of frequency controlled drives.
