Littelfuse T4800 Series User Manual
T4800 series, Generator control, Basic
Generator Control
© 2013 Littelfuse Protection Relays & Controls
Basic
T4800 SerieS
Load Sharer for Conventional Governors
Description
The T4800 Load Sharer provides automatic load sharing and
frequency control for parallel running generators. The load
sharing is proportional, meaning that the generators will be
loaded equally compared to their individual capacity.
The load on each generator is compared with the load on
the other generators and corrected until balance is obtained.
Load sharing is necessary after synchronization in order to
reestablish load balance and to obtain long term stability of
load and system frequency (compensating the droop of the
speed governor).
The T4800 has a built-in reverse power protection with
selectable limits and time delays.
Ordering Information
Simplified Circuit Diagram
FeaTureS
BeNeFiTS
Adjustable delta frequency,
stability and % load
deviation by front panel
potentiometers
Facilitates adjustment during installation and
commissioning. Load deviation adjustment
enables paralleling of differenst size
generators.
Inputs for disabling internal
frequency control
Enables operation where system frequency
is set externally such as in grid-parallel
operation
Reverse power trip
Economic solution for reverse power
protection
Visual indication of voltage,
increase/decrease and
unload signals
Provides quick and concise status
information
Direct line-line voltage
supply (up to 690 Vac)
Simplifies design and installation–no need for
PTs–or separate power supply
Galvanic isolated inputs
Protects the unit against high AC voltage and
currents from the installation including spikes
DIN rail or screw-mount
Easy installation
Features & Benefits
Other supply voltages, nominal currents and combinations are available on request.
Specifications
Max. Voltage
660 V
Voltage Range
70-110%
Consumption
Voltage 4 VA at U
N
; Current 0.4 VA at U
N
;
Continuous Current
2 x I
N
Frequency Range
35-70 Hz
Frequency Adjustment 48-62 Hz
Proportional Band
±50 - 250% load; ±5 - 25% frequency
Dead Band Zone
±2 - 10% load; ±0.2 - 1.0% frequency
Contact rating
AC: 400 V, 2 A, 250 VA
DC: 110 V, 2 A, 100 W
Operating Temperature –20°C to +70°C
Vibration Test
4 g RMS according to IEC 60068-2-64
EMC
CE according to EN50081-1, EN50082-1,
EN50081-2, EN50082-2, EN61000-6-2:1999
Approvals
Certified by major marine classification societies
Burn-in
50 hours before final test
Enclosure Material
Polycarbonate, flame retardant
Weight
0.7 kg
Dimensions
H 70 mm (2.7“); W 150 mm (5.9“);
D 115 mm (4.5“)
Installation
35 mm DIN rail or 4 mm (
3
/
16
”) screws
www.littelfuse.com/t4800
BUS
U
N
I
N
C/B
GEN
M
1
2
3
4
5
6
7
8
9
10
11
12
12
13
13
14
15
16
17 18
19
20 21
22 23 24
25
26
27
28
29
30
31 32
L
1
L
2
L
3
T4800
(Load Sharer)
UNLOAD
UNLOAD
SYNC. T4500
NEXT
T4800
COM.
PARALLEL
LINES
INCR. DECR.
REVERSE POWER
FREQ.
OUT
FREQ.
IN
FREQ.
IN
SYNC.
TRIP
AUTO
WATT
IN
TEST
OUT
–
–
+
OrderiNg
NumBer
TermiNalS
i
N
1-1
1-3
T4800.0010
450 V
400 V
5 A
T4800.0020
230 V
5 A
T4800.0030
480 V
415 V
5 A
T4800.0040
110 V
100 V
1 A
T4800.0050
450 V
400 V
1 A
T4800.0060
127 V
120 V
5 A
T4800.0070
110 V
100 V
5 A
Rev: 4-A-050313