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Electronic circuit breaker ESS31-T...-DC 24 V

1646

1

4

Operating data

DC 24 V (18...30 V)

fixed rating:

Types ESS31-TC-…:

0.5 A, 1 A, 2 A, 3 A, 3.6 A, 4 A,

6 A, 8 A, 10 A, 12 A

in ON condition: typically 8 mA

depending on the

signal output

Trip current (bimetal)

typically 0.4 A

(only in the event of a failure, until physical

disconnection)

Visual status

l

multicoloured LED:

indication

Green:

- device is ON (S1 = ON)

load circuit connected

Orange:

- overload or short circuit until

electronic disconnection

Red:

- device switched OFF electronically

load circuit OFF

OFF:

- manually OFF (S1 = OFF)

load circuit physically isolated

or device is dead-voltage

l

Potential-free signal contact

l

On/off position of the switch S1

Load circuit

Load output

power MOSFET switching output

(plus switching)

Overload and short

circuit disconnection

with active current limitation

Trip times for

see time/current characteristic

electronic disconnection

overload trip time typically 500 ms

short circuit trip time depending on

current rating (see table 1)

for physical isolation

typically 5 s

Temperature disconnection internal temperature monitoring

with physical isolation

Undervoltage

with hysteresis, no reset required:

monitoring

of load output

typically 2 ms after each ON operation,

Capacitive loads

up to 40,000 µF

Free-wheeling diode

external free-wheeling diode

recommended for inductive load

Description

ESS31-T

The model ESS31-T extends our product group of electronic over-

current protection devices for DC 24 V applications. At a width of

only 12.5 mm it provides selective protection for all DC 24 V load

circuits. This is achieved by a combination of active electronic current

limitation in the event of a short circuit and overload disconnection

at typically 1.2 times rated current. The ESS31-T is track-mountable

and provides ease of installation for groups of devices with several

circuits. DC 24 V switch-mode power supplies are widely used in

automation today. In the event of an overload, however, they turn

down the output voltage which is intended to power all connected

loads. So if there is a failure in a single load of the system, the supply

voltage will break down also in all other load circuits. Not only does

this frequently cause undefined fault conditions, but it can even lead

to machine stoppages or system downtimes.

In this context selectivity means that type ESS31-T responds faster

to any overload or short circuit conditions in a load circuit than the

switch-mode power supply. This is ensured by the combination of

active electronic current limitation and well-proven circuit breaker

technology including physical isolation.

The max. possible overcurrent is limited to typically 1.2 times rated

current (see table 1). This allows switching on capacitive loads of up

to 40,000 µF, but a disconnection will only be effected in the event of

an overload or short circuit. For adjustment to the load conditions the

current rating can be selected in fixed values from 0.5 A to 12 A. Visual

status indication is by means of a multicoloured LED and by integral

signal outputs. The manual ON/OFF switch on the device itself allows

start-up of certain individual load circuits and reset after disconnec-

tion on grounds of overcurrent.

As soon as the ESS31-T detects an overload or short circuit in its

load circuit, it blocks the load output transistor and disconnects the

current flow in the faulty circuit. After remedy of the failure, the load

output of the ESS31-T is re-activated manually by actuating the ON/

OFF switch of the device.

US patent number: US 6,490,141 B2

US patent number: US 8,237,311 B2

Features and Benefits

Approvals ESS31-TC

l

Selective load protection with physical isolation

in the event of a failure

l

All types of loads can be connected

(DC 24 V motors upon request)

l

Active current limitation when switching on capacitive loads

up to 40,000 µF and in case of overload/short circuit

l

Fixed current ratings from 0.5 A to 12 A

l

long load lines or small cable cross sections

l

Manuel ON/OFF switch (push-push actuation)

l

Clear status indication by means of LED

l

Integral fail-safe element, adjusted to current rating

l

Width per channel only 12.5 mm

l

For direct rail mounting

l

Ease of wiring via entry line busbars LINE+ and 0 V

Approval

authority

Standard

Rated voltage

Current ratings

VDE

EN 60934

DC 30 V

0.5 A…12 A

UL

UL 1077

DC 30 V

0.5 A…12 A