Power Automation and Protection Division
I.L. 40-201.9
REL 352 Version 1.00
K-3
K
A
P
P
E
N
D
I
X
3.
SQUARE WAVE DURATION
The duration of square waves used for phase comparison depends on the magnitude of IT and
the levels of KEY, LP and LN settings. The following two figures (fig. 3, 60 Hz, fig. 4, 50 Hz)
provide duration of square wave as the function of ratio of IKEY setting and IT [rms].
Figure 2. Signal Polarity
REMOTE IKEY
OUTPUT FROM
uPROCESSOR
IKEY OUT
POLARITY
INVERTED
NORMAL
TCF KEY
INPUT
TCF-10B
INVERSION
AND DELAY
TCF MARK OUT
REL 352
MARK 1 INPUT
OPTO-COUPLER
INVERSION
MARK 1 POLARITY
INVERTED
NORMAL
OPTO-COUPLER
INVERSION
SPACE 1 POLARITY
INVERTED
MARK 1 IN
SPACE 1 IN
NORMAL
REL 352
SPACE 1 INPUT
OPTO-COUPLER
INVERSION
CHANNEL FAILURE POLARITY
INVERTED
CF
NORMAL
CHANNEL FAILURE
INPUT
TCF SPACE OUT
JMP6
JMP4
JMP5
JMP1
REMOTE REL 352
LOCAL & REMOTE TCF-10B
LOCAL REL 352