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• rotection ith heavy starting
Relays T450SU can used for particularly severe starting conditions. TA450DU/SU feature convertible Manual/
Automatic reset.
In accordance with the adjacent tripping curve, the tripping time lies below the time the motor..
Ambient temperature
ABB STOTZ-KONTAKT GmbH 17
2CDC 106 014 C0203
.
•R eference num bers the PTB:
Type Reference No.. for frequent starting and braking. TA450DU/SU are suitable for protection EEx motors.
TA25..
The special relay version for EEx motors differs from the normal version follows:
• Special the tripping tim the rks
• Special order code
Tripping curves for the individual setting ranges and the PTB Approvals Certificates may ordered..5 times the setting current. See the adjacent curve for the extended range
of -25 resp.
When selecting the overload relay, check suitability the basis the tripping curves.
Exam ple :
Tripping -25 °C. Tripping occurs <1. +55 °C. They have been
tested and approved the erm National Standards Laboratory“ (PTB) Braunschweig,
Germany. Higher switching
frequencies are permitted the duty ratio and the motor starting time are allowed for and the
m otor‘s making current does not appreciably exceed times the rated operating current.4 time seconds. The relay may also used
for lower motor rated currents. TA45G PTB ATEX 3045
TA42, TA75, TABG PTB 02-32056
TA11G, TA2GG PTB 02-32057
TA45G PTB 02-32017
Limit values for tripping ambient temperatures other than °C
A bient tem perature com pensation :
The overload relays are protected against influences ambient temperature
by bimetallic compensation element which detects the ambient temperature.g. The values
for the ratio pick-up current rated current and the shortest time are crucial, and these
must specified the PTB Approval Certificate and the otor‘s rating plate..
For instance: T450TU/SU with setting range 130 . Please refer
to the adjacent diagram for guideline values for the permitted switching frequency.
• Special version EEx otors
Relays T7DM, TA25DU . The
setting range specified the rating plate inversely proportional the number cables looped
through. Applications involving operations per hour are acceptable. 92.3 ..Thermal overload relays T. The setting ranges specified
on Pages and apply non-recurrent looping through the cables..6 for looping the
cables through three times.
Example: Starting time the motor: second
Duty ratio: %
means permitted switching frequency max..5 kW, Ia/In 7.5 the cables are looped through twice; the figures are 43..e.. This achieved looping the cables through several times.. The relay must trip
within the time, i.
• Exam ple ita ility overload relay T/TA:
The motor with increased safety has the following data:
Output 7. 61.
Description
• itching frequency
Thermal overload relays cannot operated any arbitrary switching frequency order avid
tripping.
C ondition delivered :
Manual reset. Use combination thermal overload
relays and CUSTORAPID® recommended the case locked rotors motors with thermally
critical rotors. operations per hour
Use the CUSTORAPID® motor protection recommended for higher switching frequencies and
alternating loading, e.
R t:
Types E16DU, T7DU, TA25DU . the tripping curve, starting from cold state, must run below the coordinate point
Ia/In and the time.
This design means that tripping occurs between and +40 within the
ranges defined IEC 947-4-1... 185 also suitable for currents of
65
