ABB SYN 5201 Operating Instructions Manual page 9

Operating Instructions
2.2.1 Measuring
The following measured variables are generated from the two single-phase measuring
voltages:
Voltage U1, U2
U1 is the reference voltage e.g. line
U2 is the adjustable voltage e.g. generator.
Frequency f1, f2
f1 is the reference frequency
f2 is the adjustable frequency.
Voltage difference  U
U = IU1I – IU2I
U > 0
Adjustable voltage is lower
U < 0
Adjustable voltage is higher
Slip s

f 1 f

s
f 1
s > 0 Adjustable frequency is less (e.g. generator is sub-synchronous)
s < 0 Adjustable frequency is greater (e.g. generator is oversynchronous)
Phase-angle difference 
  
 
1
 > 0
Adjustable frequency is lagging
 < 0
Adjustable frequency is leading
Acceleration ds/dt

ds / dt 2 *
(Every 0.5 s, an average value is formed from 56 measurements; sampling period:
9 ms)
ds/dt > 0 Adjustable frequency is reduced (e.g. generator accelerates)
ds/dt < 0 Adjustable frequency increases (e.g. generator is slowed down)
With SYN 5202, the measurement is carried out separately for each channel. It is
possible to carry out three-phase measurements in order to detect connection faults
(rotary field, polarity) and losses of phase.
abb
ABB Switzerland Ltd
Template: CHIND Techn doc stand, A4 P de, R1.DOT; Filename: 3BHS109762E01 D.doc; Print: 12/6/2011 5:48:00 PM; Save: 12/1/2011 2:37:00 PM; CHIND No. 3BHS109763 ZAB D14 Rev. -; I-Q
2
* 100 %
2

x 56
  

s % / s
x

x 1
Document No Art Part
3BHS109762 E01
SYN 5201/SYN 5202
Language Revision page
en D 9