Watlow Series 988 - Manual (Page 20)

Figure 2.10b —
Current Transformer Input
98 _ _ - _ 4 _ _ - _ _ _ _
The current transformer must be purchased separately. Watlow current
transformer part number is 16-0246 (up to 50 amps)..
Systems that use more than 50 Amps need an interstage transformer.
For example, if you use a 300A current transformer, part #16-0073, and
an interstage transformer, part #16-0176, the 300A current transformer
provides a 5A signal to the interstage transformer. In turn, the transformer
sends a 20mA maximum signal to the controller.
20
19
T3
T1
T2
Phase
dot
2.10 WATLOW Series 988 User’s Manual Installation and Wiring, Chapter 2
Input 2 Wiring
20
19
L2
L1
CT
Load wire
Center leg not used
Figure 2.10a —
Slidewire Feedback or Potentiometer Input
98 _ _ - _ 3 _ _ - _ _ _ _
19
20
18
CW
CCW
Wiper
NOTE:
See Chapter 8 for
information on
slidewire feedback.
˜
NOTE:
A process output
cannot be installed
on output 1 when
using a current
transformer input.
NOTE:
Successful installa-
tion requires five
steps:
• Model number and
software choice
(Appendix);
• DIP switch set-
tings (Chapter 1);
• Sensor match
(Chapter 2 and
Appendix);
• Sensor installation
(Chapter 2); and
• Wiring (Chapter 2).
AC Load
19
20
0 to 5A
AC
0 to
20mA
A
Bk
Red
Red
Wh Bk
Bk Wh
Bk
16-0176
Transformer
CT
T1
T3
T2
5A
20mA
19
20
Single-phase Single-phase current sensing up to 300 amps
3-phase using 2 current transformers 3-phase current sensing up to 300 amps