Current and Voltage Controls
3-Phase Voltage Sequence Control
Type SM 170
• 3-phase monitoring relay for phase
sequence/phase loss
• Measures when all 3 phases are present and
have the correct phase sequence
• Output: 10 A SPDT relay
• Plug-in type module
• S-housing
• LED-indication for power supply and output ON
• Power supply is the 3-phased measuring voltage
Product Description
3-phase plug-in monitoring
and phase sequence/phase-
loss relay. Frequently used to
prevent a 3-phase motor from
running on only 2 phases or
to secure the right phase se-
quence when connecting a
load to the mains.
Ordering Key
Housing
Function
Output
Type
Power supply
SM 170 400
Type Selection
Plug
Circular
Output
SPDT
Supply: 220 VAC
SM 170 220
Supply: 380 VAC
SM 170 380
Supply: 400 VAC
SM 170 400
Supply: 415 VAC
SM 170 415
Input Specifications
Input
Pin 5
Pin 6
Pin 7
Pin 11
Phase L1
Phase L2
Phase L3
Neutral (optional connection)
measures on own supply
Output Specifications
Output
Rated insulation voltage
Contact ratings
(AgCdO)
Resistive loads
AC 1
DC 1
or
Small inductive loads AC 15
DC 13
Mechanical life
Electrical life
AC 1
Operating frequency
Dielectric strength
Dielectric voltage
Rated impulse withstand volt.
SPDT relay
250 VAC (rms)
(cont./elect.)
µ (micro gap)
10 A/250 VAC (2500 VA)
1 A/250 VDC (250 W)
10 A/25 VDC (250 W)
2.5 A/230 VAC
5 A/24 VDC
≥
30 x 10
6
operations
≥
2.5 x 10
5
operations
(at max. load)
≤
7200 operations/h
≥
2 kVAC (rms) (cont./elect.)
4 kV (1.2/50 µs) (cont./elect.)
(IEC 60664)
Supply Specifications
Power supply AC types
Rated operational voltage
Through pins 5, 6, 7 & 11
220
380
400
415
Internal measuring circuit is
connected to pins 5 & 7
Voltage interruption
Dielectric voltage
Rated impulse withstand volt.
Overvoltage cat. III (IEC 60664)
(IEC 60038)
3 x 220 VAC ± 15%, 45 to 65 Hz
3 x 380 VAC ± 15%, 45 to 65 Hz
3 x 400 VAC ± 15%, 45 to 65 Hz
3 x 415 VAC ± 15%, 45 to 65 Hz
Rated operational power
≤
40 ms
None (supply/elect.)
4 kV (1.2/50 µs) (line/neutral,
line/line), direct connection
to electronics
2.5 VA
Specifications are subject to change without notice
1
SM 170
General Specifications
Reaction time
Indication for
Power supply ON
Output ON
Environment
Degree of protection
Pollution degree
Operating temperature
Storage temperature
Weight
Approvals
τ
= 0.5 s, worst case reac-
tion time may be up to 5 x
τ
LED, green
LED, red
(IEC 60947-1)
IP 20 B (IEC 60529)
(IEC 60664)
1: SM 170 380/400/415
2: SM 170 220
-20° to +50°C (-4° to +122°F)
-50° to +85°C (-58° to +185°F)
200 g
UL, CSA, SEV
(SEV only 3 x 220 VAC)
Mode of Operation
The relay measures on its own
3-phased power supply and
operates when all phases are
present and the phase se-
quence is correct.
Example 1
The relay is for monitoring
that the power supply has a
correct phase sequence and
that all phase voltages are
present. The relay is a 3-phase
power supply monitoring re-
lay.
Example 2
The relay releases in case of
interruption of one of the
phases, provided that the
voltage regenerated by elec-
tric motors on the interupted
phase does not exceed 70%
of the nominal voltage. If it
exceeds this value the con-
nection cannot be recom-
mended (see description ex.
3). The regenerated voltage
will be a lower phase voltage
combined with a phase angle
failure.
Example 3
If the value of the regene-
rated voltage is slightly higher
than 70% of the nominal volt-
age, the relay releases when
neutral is connected to pin 11
as sensitivity is improved.
Wiring Diagrams
Example 1
Example 2 and 3
Accessories
Sockets◊
Hold down spring◊
Mounting rack
Socket covers
Front mounting bezel
S 411
HF
SM 13
BB 4
FRS 2
For further information refer to "Accessories".
Operation Diagram
Phase L1, pin 5
Phase L2, pin 6
Phase L3, pin 7
Relay ON
2
Specifications are subject to change without notice