Toshiba TE2 Series - Page 90

TE2 Series Digital Solid State Soft Starter User Manual 81 | Page
Appendix 4 (cont.) External OL Relay Applications
Across-the-Line (Direct-on-Line) Bypass
A suggested control schematic is shown below for using the TE2 …-BP
Series rated for Across-the-Line Bypass with an External Overload:
Figure APP4.2: TE2 Wiring for Across-the-Line Bypass Operation with External Overload Relay
(Only the terminals necessary for this operation are shown)
In this example:
The Start / Run command (2-wire or 3-wire) energizes a control Relay
“CR”. If the selector Switch is in the “SS” (Soft Start) position, the CR
contact closes the 24VDC control signal to TB1, terminals 1 & 3 of the
TE2 Series and begins ramping. When At-Speed is reached, an internal
Bypass Relay closes the Bypass Contactor. While in this mode, the
CPU provides full motor protection, even in bypass.
When the Selector Switch is placed in the “A-T-L” (Across-the-Line)
position, a 2
nd
isolated contact of CR closes between B1 and B2 of TB4
which are internally connected in parallel to the Bypass Relay contact in
the Bypass Contactor coil circuit. Since the TE2 electronics may be out
of service, an External Overload is added which operates in this mode
and protects the motor by dropping out the connection between B1 and
B2.
Caution:
The circuit on TB-4, is at the same potential as the AC control
voltage, but should not be directly connected to it. PC board
damage may result.
TE2
Starte
r
.
Bypass
Contactor
"BP"
Disconnect
o
r
Circuit
Breake
r
Solid State
.
Over Load .
MTR
G
R /
L1
T
/
L3
S /
L2
U /
T1
W /
T3
V /
T2
External
Over Load
Of
f
S S A-T-L
1 2 3
A1 A2
A
C CONTROL POWER
Start / Run
Command
External
OL
TE2 ...-BP Series
Internal Wiring
TE2 -TB-1
(24VDC)
TE2 -
TB-2
Bypass
Contactor
Coil
CR
C
R
B1 B2
Internal Bypass
Pilot Relay
AC
Control Powe
r
Potential
TE2 -
TB-4
BP
(2-wire or 3-wire)
97 98
CR