GE Industrial Solutions ZBTSCTH SERIES 100 - 4000 AMPS - Manual (Page 18)

ZBTSCTH Operation and Maintenance Manual (46R-7000) 16 Zenith Controls, Inc.
SECTION IV - ADJUSTMENTS AND SETTINGS (Continued)
1. PARALLELING RELAY SETTINGS
25, 27/59N & 27/59E are factory set to allow
paralleling of the sources only when these
conditions have been met:
a. Phase Angle Differences < 5° (@ 0.1 Hz f)
b. Frequency Difference < 0.2 Hz
c. Voltage Difference < ±5% Nominal
NOTES:
1. This system requires an isochronous
governor with an operating frequency of
60 ± 0.2 Hz.
2. Requires a shunt trip breaker on generator set
with a response time not exceeding 50 ms.
2. SOLID STATE TIMERS
Solid state timers are adjustable from 0.1 second
to 100 hours. The red timing indicator in the
upper left corner flashes as the timer progresses
through the timing cycle. When the timing cycle
is completed, the indicator remains illuminated. A
flathead screwdriver is required to change the
setting, as shown in Figure 5 below.
CAUTION !
Do NOT change the setting while the timer is
energized. Timer malfunction or damage may
The time unit is selected by turning the rotary
switch at the lower right of the timer. Four
selections are available: “Seconds”, “Minutes”,
“Hours”, “10 Hours”. The time unit selected is
displayed in the window below the time setting
dial.
The time range is selected by turning the rotary
switch at the lower left of the timer. Four ranges
are available: “0-0.5”, “0-1.0”, “0-5.0”, “0-10.0”.
The dial digits appear in the windows around the
time setting knob.
Figure 5
The factory setting of the solid state timers used
in the Zenith standard package are shown in
Table 5 below.
Timer Factory Setting
T
U
W
DT
DW
ST
PART
OLC
ETT
30 minutes
5 minutes
1 second
5 seconds
5 seconds
1 second
0.002 sec,
0.275 sec.
0.420 sec.
3. VOLTAGE/FREQUENCY SENSOR
(VFSM)
The pickup point may be adjusted by rotating the
adjustment screw as shown in Figure 6 below.
Counter-clockwise rotation increases the pickup
voltage.
Table 5
Pickup Voltage (at 100% Frequency)
Adjustable:
80% to 95%
Factory Set: 90%
Pickup Frequency
Adjustable:
80% to 100%
Factory Set: 95%
Figure 6