Specifications are subject to change without notice 1
Current and Voltage Controls
• 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
Ordering Key
Housing
Function
Output
Type
Power supply
Type Selection
Plug Output Supply: 220 VAC Supply: 380 VAC Supply: 400 VAC Supply: 415 VAC
Circular SPDT SM 170 220 SM 170 380 SM 170 400 SM 170 415
Input Specifications
Input
Pin 5 Phase L1
Pin 6 Phase L2
Pin 7 Phase L3
Pin 11 Neutral (optional connection)
measures on own supply
Output SPDT relay
Rated insulation voltage 250 VAC (rms)
(cont./elect.)
Contact ratings (AgCdO) µ (micro gap)
Resistive loads AC 1 10 A/250 VAC (2500 VA)
DC 1 1 A/250 VDC (250 W)
or 10 A/25 VDC (250 W)
Small inductive loads AC 15 2.5 A/230 VAC
DC 13 5 A/24 VDC
Mechanical life ≥30 x 106operations
Electrical life AC 1 ≥2.5 x 105operations
(at max. load)
Operating frequency ≤7200 operations/h
Dielectric strength
Dielectric voltage ≥2 kVAC (rms) (cont./elect.)
Rated impulse withstand volt. 4 kV (1.2/50 µs) (cont./elect.)
(IEC 60664)
running on only 2 phases or
to secure the right phase se-
quence when connecting a
load to the mains.
Power supply AC types Overvoltage cat. III (IEC 60664)
Rated operational voltage (IEC 60038)
Through pins 5, 6, 7 & 11
220 3 x 220 VAC ± 15%, 45 to 65 Hz
380 3 x 380 VAC ± 15%, 45 to 65 Hz
400 3 x 400 VAC ± 15%, 45 to 65 Hz
415 3 x 415 VAC ± 15%, 45 to 65 Hz
Internal measuring circuit is
connected to pins 5 & 7
Voltage interruption ≤40 ms
Dielectric voltage None (supply/elect.)
Rated impulse withstand volt. 4 kV (1.2/50 µs) (line/neutral,
line/line), direct connection
to electronics
Rated operational power 2.5 VA
3-Phase Voltage Sequence Control
Type SM 170
Output Specifications
Supply Specifications
SM 170 400
2Specifications are subject to change without notice
SM 170
Reaction time τ= 0.5 s, worst case reac-
tion time may be up to 5 x τ
Indication for
Power supply ON LED, green
Output ON LED, red
Environment (IEC 60947-1)
Degree of protection IP 20 B (IEC 60529)
Pollution degree (IEC 60664)
1: SM 170 380/400/415
2: SM 170 220
Operating temperature -20° to +50°C (-4° to +122°F)
Storage temperature -50° to +85°C (-58° to +185°F)
Weight 200 g
Approvals UL, CSA, SEV
(SEV only 3 x 220 VAC)
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
Mode of Operation
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.
Operation Diagram
Phase L1, pin 5
Phase L2, pin 6
Phase L3, pin 7
Relay ON
Wiring Diagrams
Sockets◊S 411
Hold down spring◊HF
Mounting rack SM 13
Socket covers BB 4
Front mounting bezel FRS 2
For further information refer to "Accessories".
Accessories
Example 1 Example 2 and 3
General Specifications
