Littelfuse T3000 User Manual

Protection Relays & Controls

Generator & Single-Function Protection–Frequency

T3000 SERIES

Frequency Relay

Simplified Circuit Diagram

T3000

(Frequency Relay)

(L)

L

1

(N)

L

2

1
2
3

UNDERFREQUENCY

OVERFREQUENCY

ALARM

ALARM

Ordering Information

ORDERING NUMBER

1-3 2-3

T3000.0010 230 V
T3000.0020 450 V 400 V
T3000.0030 110 V 100 V
T3000.0040 480 V 415 V
T3000.0050 127 V 120 V

Other vo ltages are available o n request .

TERMINALS

10

9
8

7
6
5

Description

The T3000 Frequency Relay is designed for frequency
monitoring on generators, bus bars or other distribution
systems.

The T3000 consists of two circuits, one circuit for over
frequency and one for under frequency monitoring. Each
circuit has individual settings for frequency levels and time
delays. The output relays are normally energized output
relays. The output relay for under frequency is activated at
frequencies higher than the preset value, while the output
relay for over frequency is activated at frequencies lower
than the preset value. This means that both output relays are
activated at frequencies within the interval between the under
and over frequency scale range.

Features & Benefits

FEATURES BENEFITS

Accepts high supply
voltage variation

Visual indication of power,
pick-up, and output trip

Direct line-line or line­neutral voltage supply (up
to 690 Vac)

Combining 2 relays in
same enclosure

Galvanic isolated inputs

DIN-rail or screw-mount
& adjustment by
potentiometers

Ensures correct operation in spite of voltage
supply fluctuations (fulfills marine class
requirement)

Provides quick and concise status information

Simplifies design and installation.
No need for PTs.

Economic solution . Monitoring both
underfrequency and overfrequency in same unit,
and occupying less space in the switch panel

Protects the unit against high AC voltage and
currents from the installation including spikes

Easy installation

Specifications

Overfrequency Level 45-65 Hz
Delay 1-10 sec.
Underfrequency Level 45-65 Hz
Delay 1-10 sec.
Max. Voltage 660 V
Voltage Range 70 -110%
Consumption
Continuous Current 2 x I
Frequency Range 40 -70 Hz
Output Relay Normally energized
Contact Rating AC: 250 V, 2 A, 250 VA; DC: 60 V, 2 A, 100 W
Overall Accuracy ±3% of highest value
Repeatability ±1%
Operating Temperature
Dielectric Test 2500 V, 50 Hz
EMC CE according to EN50081-1, EN50082-1, EN50081-2,

EN50082-2

Approvals Certified by major marine classification societies
Burn-in 50 hours before final test
Enclosure Material Polycarbonate. Flame retardant
Weight 0.5 kg
Dimensions H 70 mm (2.76”); W 100 mm (3.94”); D 115 mm (4.52”)
Installation 35 mm DIN rail or 4 mm (

5 VA at U

N

N

–20°C to + 70°C

3

/16”) screws

© 2013 Littelfuse Protection Relays & Controls
Littelfuse.com/t3000

Rev: 4-A-050213