Reyrolle

Protection
Devices

7SR17 Rho
Motor Protection Relay

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Siemens Protection Devices Limited 2
7SR17 Rho Supervision (can include)
Motor Protection Relay
46PhRev Phase Reversal
50BCL Breaking Capacity Limit
50BF Circuit Breaker Fail
60CTS-I CT Supervision
60CTS Enhanced CT Supervision
60VTS VT Supervision
74T/CCS Trip Circuit Supervision
81B Anti Backspin
Temp Temperature Input Monitoring (via RS485
comms port)

Control (can include)

86 Lockout
Motor Start/Stop Control
Fig 1. 7SR17 Rho Fascia User Programmable Logic

Features
4 Settings Groups
Description Password Protection – 2 levels (protection and control)
Self Monitoring

The 7SR17 motor protection relay range utilises service and

design experience accumulated with the previous
generations of Rho family of products. User Interface
Housed in 4U high, size E4 cases, the 7SR17 Rho can provide
protection, control, monitoring, instrumentation and
metering with integrated input and output logic, data 20 character x 4 line backlit LCD
Menu navigation keys
logging and fault reports.
9 Programmable Tri-colour LEDs
Relay functionality is accessed via a familiar user friendly
interface.
Communication access to relay functionality is via a front
USB port for local PC connection or rear RS485 port for
remote connection. Additional rear port options are
Monitoring Functions
available.
Monitoring Functionality (can include)
Phase, earth and sequence currents
Function Overview Thermal equivalent and phase difference currents
Line, phase, neutral and sequence voltages
Power - Apparent, Real and Reactive. Power factor
Protection (can include) Energy - WHr and VAr Hr
14 Stall Protection Demand metering
46 Phase Unbalance Protection Start/Run Monitoring Profiles:
49 Thermal Overload Number of Starts, Starts per hour
48/66 Start Protection Start currents, voltages and power
Start method (Local/remote/comms)
37 Undercurrent Motor run / start / trip times, thermal status,
67/50, 67/51 Directional Overcurrent Binary Input / Output status
67G/67N Directional Earth Fault General Alarms inc. trip circuit healthy/failure
87REF High Impedance REF Starters
Fault data
27/59 Under/Over Voltage CB trip and maintenance counters and Time to Trip
47 NPS Voltage/Phase Reversal Temperature input (optional) values
81 Under/Over Frequency

32 Power
32S Sensitive Power
55 Power Factor

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 Data Communications Description of Functionality
Standard Communications Ports With reference to figures 7 & 8 ‘Function Diagrams’.
Communication access to relay functionality is via a front
USB port for local PC connection or rear electrical RS485 port 14 Stall Protection
for remote connection Each element has a single definite time overcurrent charac-
teristic with settings for pickup level and Definite Time Lag
Protocols (DTL) delays.
IEC60870-5-103, Modbus RTU, DNP3.0. User selectable with Operation can be controlled from motor stopped or running
programmable data points. conditions.
Modbus RTD Client for use with external temperature
monitoring interface. 37 Undercurrent
Each element has settings for the pickup level and the defi-
Data nite time lag (DTL) delay. The element operates when cur-
Up to 1000 event records rent falls below setting for the duration of the delay.
User configurable fault record duration
Waveform records 46 Phase Unbalance Protection
Measurands Unbalance current has a significant heating effect on the
Commands motor.
Time synchronism Two phase unbalance measurement modes are available.
Viewing and changing settings Either NPS current or the difference between maximum and
minimum phase currents can be used as a measurement of
the unbalance level.
Inverse or definite time operation can be selected.

48/66 Start Protection

The feature provides settings to control both the number of
times a motor can be started within a specified time period
and the minimum time between starts. Motor starting can
be inhibited when this limit is reached.
Motor start time can also be monitored.

49 Thermal Protection – Rotating Plant

The enhanced thermal algorithm provides compliance with
IEC60255-8 (Thermal Electrical relays).
The operating curves take into account the effects of present
loading, prior loading and unbalanced currents on the motor
operating temperature.
A user definable thermal curve is selectable to allow match-
ing of the relay thermal characteristic to all motor and cool-
ing system types.
‘Starting’ and ‘cooling’ constants modify the thermal charac-
teristic during motor run-up and stopped conditions.

Temperature Inputs
Motor resistance temperature detectors (RTDs) can be con-
nected via an optional external 7XV5662-6AD10 Tempera-
ture Monitoring Interface. Up to twelve Pt100 sensors can be
monitored.
The interface is connected to the COM1-RS485 port of the
relay.

50/51, G/N Earth Fault

Two earth fault measurement modes are available.
Measured earth fault mode (G) directly measures the earth
current from an independent CT, or the residual connection
of the 3 line CT’s.
Derived earth fault mode (N) derives the earth current inter-
nally from the line CT inputs
Independent settings are available for pickup current and
time-delays.
IDMT curves are available.

Siemens Protection Devices Limited 4

50/51 Overcurrent
Definite time elements provide short circuit overcurrent Optional Functionality
protection with independent settings for pickup current and
time-delays.
27/59 Under/Over Voltage
IDMT curves can also be selected.
Each element has settings for pickup level, drop-off level and
50BF Circuit Breaker Fail Definite Time Lag (DTL) delayed operation.
The circuit breaker fail function may be triggered from an The elements can be independently selected to under or
internal trip signal or from a binary input. Where a CB closed over voltage operation.
is detected following a trip signal an output is issued after a
specified time interval. This can be used to re-trip the CB or 32 Power
to back-trip an upstream CB. A second time delay is available This feature can be used to detect loss of motor load.
to enable another stage to be utilized if required. Each element can be set to measure real, apparent or reac-
tive power and has independent settings for pickup level and
60CTS CT Supervision Definite Time Lag (DTL) delayed operation.
Two types of CT wiring monitoring is available dependent on
the availability of VT inputs: 32S Sensitive Power
60CTS-I determines CT failure from a comparison of phase Sensitive power is measured from the 4th CT input (IG) and
current levels. user selected voltage inputs.
Where VT inputs are available 60CTS considers the presence Each element can be set to measure real, apparent or reac-
of negative phase sequence current, without an equivalent tive power and has independent settings for pickup level and
level of negative phase sequence voltage. Definite Time Lag (DTL) delayed operation.
The element has user operate and delay settings.
47 Negative Phase Sequence (NPS) Overvoltage
81B Anti Backspin Unbalance (NPS) voltage can be caused by uneven system
To inhibit attempted restarting of the motor until after the loading.
rotor has completely stopped backspin protection is applied. Each element has independent settings for pickup level and
Starting is inhibited until the 81B time delay has elapsed. Definite Time Lag (DTL) delayed operation.

87REF High Impedance REF 55 Power factor

The 87REF function can provide high speed earth fault pro- This feature is used to monitor motor operating conditions.
tection for motor winding faults. This function requires an Each element has independent settings for pickup level and
external series stabilising resistor and voltage limiting non- Definite Time Lag (DTL) delayed operation.
linear resistor.
60VTS VT Supervision
74TCS Trip Circuit Supervision The VT Supervision uses a combination of sequence compo-
The trip circuits can be monitored via binary inputs connect- nent voltage and current to detect a VT fuse failure.
ed in H4/H5/H6 or H7 schemes. Trip circuit failure raises an This condition can provide an output for indications/alarms
HMI alarm and output(s). or used to inhibit voltage dependent functions. Element has
user operate and delay settings.
Programmable User Logic
The user can map Binary Inputs and Protection operated 67 Directional Control for Overcurrent and Earth Fault
outputs to Function Inhibits, Logic Inputs, LEDs and/or Binary Directional control can be used to provide additional protec-
Outputs. tion discrimination e.g. correct discrimination for earth
The user can also enter up to 4 equations defining scheme faults in non-effectively earthed systems with appreciable
logic using standard functions e.g. Timers, AND/OR gates, capacitance.
Inverters and Counters.
Each Protection element output can be used for 81 Under/Over Frequency
Alarm/Indication and/or tripping.
Frequency elements can be used to monitor suuply quality
e.g. under-frequency causing motor deceleration.
Function LED’s
Each element has independent settings for pickup level,
Ten user programmable tri-colour LED’s are provided
drop-off level and Definite Time Lag (DTL) delayed opera-
eliminating the need for separate panel mounted indicators
tion.
and associated wiring. Each LED can be user set to red, green
or yellow allowing for indication of the associated function’s
status. A slip-in pocket adjacent to the LEDs enables the user
to insert customised labels. A printer compatible template is
available.

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 Data Acquisition - Reydisp Evolution
Via Communication Interface

Sequence of event records

Up to 1000 events are stored and time tagged to 1ms
resolution.

Fault Records
The last 10 fault records are displayed on the HMI, with time
and date of trip, measured quantities and type of fault.

Waveform recorder
The waveform recorder stores analogue data for all phases,
the states of protection functions, Binary Inputs, LEDs and
Binary Outputs with pre & post trigger data. A record can be
triggered from Protection function, Binary input or via data
communications. 1 record of 10sec, 2 of 5sec, 5 of 2sec or
10 records of 1 second are stored. The ratio of pre-fault to
post fault storage can be set by the user.
Fig 3. Typical Reydisp Evolution screenshot
Data Log
Provides a rolling record of line currents and voltage (where Reydisp Evolution is common to the entire range of Reyrolle
applicable) over a user selectable period of time. numeric products. It provides the means for the user to apply
settings interrogate settings and retrieve events and
disturbance waveforms from the relay.
Reydisp Evolution installation includes the Communications
Editor to allow configuration of the serial protocol data points
Serial Communications and options, the Curve Editor to allow programming of user
defined TCC characteristics and the Language Editor to allow
relay display text to be edited. This can be used to provide non-
The relay offers a USB serial port as standard on the front of English language support using the European character set.
all units. All of the relays functions can be set on a PC using
Reydisp Evolution via the relay USB port. The connection is
made with a USB cable and operates as ‘plug and play’, so no
pre-setting of the relay is required.
The front port can be switched off or set to use either the Reydisp Manager
MODBUS-RTU, IEC60870-5-103, DNP3.0 (optional) or ASCII
protocols for testing purposes.
A rear RS485 electrical connection is available on all units for Reydisp Manager provides the functionality of Reydisp
system interface connections. An internal terminating Evolution and also provides access to user logic within the
resistor is provided, which can be connected into the circuit relay via an easy to use graphical interface.
by adding a wire loop between the relevant terminals.

Fig 2. Typical RS485 connection

The rear RS485 can be user selected to be OFF, IEC60870-5-

103, MODBUS RTU or optional DNP3.0 protocol.

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 Binary Inputs
Technical Data
Operating Voltage 19V: Range 17 to 320V dc
For full technical data refer to the Performance Specification 19V: Range 92 to 138 V ac
Section of the Technical Manual. 88V: Range 74 to 290V dc
Maximum dc current for 1.5mA dc
operation 1.5mA peak ac

Binary Outputs
Inputs and Outputs
Operating Voltage Voltage Free
Operating Mode User selectable - Self or
Current Inputs
Hand Reset
Contact Operate / Release 7ms / 3ms
Quantity 3 x phase, 1 x SEF Time.
Rated Current IN 1/5A Making Capacity:
Measuring Range 80 xIn Carry continuously 5A ac or dc
Instrumentation 0.1xIn ±1% In or ±10 mA Make and carry 20A ac or dc for 0.5s
Frequency 50/60Hz (L/R 40 ms and V 300 V) 30A ac or dc for 0.2s
Thermal Withstand: Breaking Capacity
Continuous 4.0 x In ( 5 A and 300 V):
1 Second 100A (1A) 350A (5A) AC Resistive 1250VA
Burden @ In 0.1VA (1A phase and Earth AC Inductive 250VA at p.f. 0.4
element) DC Resistive 75W
0.3VA (5A phase and earth DC Inductive 30W at L/R 40ms
element) 50W at L/R 10ms

Voltage Inputs

Quantity 3 (Optional)
Rated Voltage Vn 40 – 160V
Instrumentation 0.1xVn ±1% Vn or ±10 mV
Frequency 50/60Hz
Thermal Withstand: 300V rms
Continuous
Burden @ 110V 0.6VA

Auxiliary supply

Nominal voltage Operating Range V

24 to 60V dc 18 to 72V dc
80 to 250V dc 64 to 300V dc
115V ac 92 to 138V ac
Allowable superimposed ac 12% of DC voltage
component
Allowable breaks/dips in 50ms
supply (collapse to zero)

Auxiliary supply: Burdens

Power Consumption Minimum Maximum

DC 3.9W 8.0W
AC 9VA 0.5PF 15VA 0.5P

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 Electrical Fast Transient / Burst Immunity
Mechanical Tests IEC 60255-22-4 Class A (2002)

Vibration (Sinusoidal) Type Level Variation

Case, Aux Power & I/O 4.0kV 10%
IEC 60255-21-1 Class I
RS485 Comms 2.0kV No data loss
Type Level Variation
Surge Immunity
Vibration response 0.5gn 5%
Vibration endurance 1.0gn 5% IEC 60255-22-5

Shock and Bump Type Level Variation

Analog Inputs. 4.0kV
IEC 60255-21-2 Class I
Line to Earth
Case, Aux Power & I/O. 2.0kV
Type Level Variation
Line to Earth
Shock response 5gn, 11ms 5% 10%
Analog Inputs. 1.0kV
Shock withstand 15gn, 11ms 5% Line to Line
Bump test 10gn, 16ms 5% Case, Aux Power & I/O. 1.0kV*
Line to Line
Seismic RS485 Comms port. 1.0kV No data loss
IEC 60255-21-3 Class I Line to Earth
*Note 45ms pick up delay applied to binary inputs
Type Level Variation
Seismic response 1gn 5% Conducted Radio Frequency Interference
IEC 60255-22-6
Mechanical Classification
Type Level Variation
Durability >106 operations 0.15 to 80MHz 10V 5%

Radiated Radio Frequency

IEC 60255-25
Electrical Tests Type Limits at 10m, Quasi-peak
30 to 230MHz 40dB( V/m)
Insulation 230 to 10000MHz 47dB( V/m)
IEC 60255-5
Conducted Radio Frequency
Type Level
Between any terminal and earth Type Limits
2.0kV AC RMS for 1min Quasi-peak Average
Between independent circuits
Across normally open contacts 1.0kV AC RMS for 1min 0.15 to 0.5MHz 79dB( V) 66dB( V)
0.5 to 30MHz 73dB( V) 60dB( V)

Radiated Immunity
High Frequency Disturbance
IEC 60255-22-3 Class III
IEC 60255-22-1 Class III
Type Level Variation
Type Level Variation 80MHz to 1000MHz 10V/m 5%
Case, Aux Power & I/O. 2.5kV 10%
Common mode Magnetic Field with Power Frequency
Case, Aux Power & I/O. 1.0kV 10%
IEC 61000-4-8, Class V
Transverse mode
RS485 Comms 1.0kV No data loss
Type Level
Electrostatic Discharge 100A/m (0.126mT) continuous 50Hz
IEC 60255-22-2 Class IV 1000A/m (1.26mT) for 3s

Type Level Variation

Contact discharge 8.0kV 5%

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 Environmental Tests Performance
Temperature 14 Stall Protection
IEC 60068-2-1/2
Number of Elements 4
Operating Range -10 C to +55 C Setting Range Is: - 0.05 to 10 x In
Storage range -25 C to +70 C Time Delay 0.00 to 14400s
Operate Level 100% Is ±5% or ±1% xIn
Humidity Operate time
IEC 60068-2-78 2 x Is 35ms ± 10ms,
5 x Is 25ms ± 10ms
Operational test 56 days at 40 C and 93% relative Operate time following tbasic +td , ±1% or ±10ms
humidity delay
Controlled by Stopped, No acceleration,
IP Ratings Running, None
IEC 60529
27/59 Under/Over Voltage
Type Level
Installed with cover IP 51 from front of relay
Number of Elements 4 Under or Over
Installed with cover removed IP 20 from front of relay Operate Any or All phases
U/V Guard 1 to 200V
Setting Range Vs 5 to 200V
For full technical data refer to the Performance Specification
Hysteresis Setting 0 to 80%
Section of the Technical Manual.
Operate Level Vop 100% Vs ±1% or ±0.25V
Reset Level: -
Undervoltage (100% + hyst) x Vop ±1% or ±0.25V
Overvoltage (100% - hyst) x Vop ±1% or ±0.25V
Delay Setting td 0 to 14400s
Basic Operate Time: -
1.1xVs (OV) 73ms ±10ms
2.0xVs (OV) 63ms ±10ms
0.5xVs (UV) 58ms ±10ms
Operate time tbasic +td , ±1% or ±10ms
following delay.
Inhibited by Binary or Virtual Input
VT Supervision, Voltage Guard

32 Power

Number of Elements 2 Forward or Reverse

Operate P, Q or S
U/C Guard 0.05 to 1.0 x In
Setting Range Ss 0.05 to 2.0 x Sn
Operate Level Sop 100% Ss, ± 5% or ± 2% Sn
Reset Level: - 95% Sop
Basic Operate Time: -
1.1 x Ss (over) 60ms ± 10ms
2.0 x Ss (over) 45ms ± 10ms
0.5 x Ss (under) 30ms ± 10ms
Delay Setting td 0 to 14400s
Operate time tbasic +td , ±1% or ±10ms
following delay.
Inhibited by Motor not running, VTS

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32S Sensitive Power 48/66 Start Protection

Number of Elements 2 Forward or Reverse Max. No. of Starts OFF, 1 to 20

Operate P, Q or S Max. Starts Period 1 to 60 minutes
U/C Guard 0.005 to 1.0 x In Start Inhibit Delay 1 to 60 minutes
Setting Range Ss 0.005 to 2.0 x Sn Time Between Starts OFF, 1 to 60 minutes
Operate Level 100% Ss ± 5% or ± 2% Sn
Reset Level: - 95% Sop
Basic Operate Time: - 49 Thermal Protection
1.1 x Ss (over) 60ms ± 10ms
2.0 x Ss (over) 45ms ± 10ms Setting Range Itheta 0.1 to 3.0 x In
0.5 x Ss (under) 30ms ± 10ms NPS Weighting Factor (K) 0.1 to 10.0 0.1
Delay Setting td 0 to 14400s TauH Heating Constant 0.5 to 1000 mins, 0.5 mins
Operate time tbasic +td ± 1% or ± 10ms
TauS Starting Constant 0.005 to 1.0 x TauH , 0.005
following delay.
TauC Cooling Constant 1 to 100 x TauH , 1
Inhibited by Motor not running, VTS
Hot/cold ratio OFF, 1 to 100%, 1%
Operate Level 100% Is, ±5% or ±1% x In
37 Undercurrent Operate time 2
I EQ 1
H
I p2
C
t In 2
I EQ I2
Number of Elements 2
U/C Guard 0.05 to 5.0 x In ±5% or ±100ms
Setting Range Is 0.05 to 5.0 x In (Itheta = 0.3 to 3 x In)
Operate Level 100% Is ± 5% or ± 1% xIn (1.2 to 20 x Itheta)
Delay Setting td 0 to 14400ss User defined
Basic Operate Time: - Capacity Alarm Level Disabled, 50,51…100%
0.5 x Is 35ms ± 10ms Load Alarm Level OFF, 0.5 to 1.0 x Itheta , 0.05
Operate time following tbasic + td , ± 1% or ± 10ms Thermal restart inhibit 20 to 100%, 1%
delay. Inhibited by Binary or Virtual Input
Overshoot Time < 40ms
Inhibited by Binary or Virtual Input
50 (67) Instantaneous/DTL OC & EF (Directional)

46 Phase Unbalance Protection Operation Non directional, Forward or

reverse
Number of Elements 1 (Magnitude difference or NPS) Elements Phase (50), Derived Earth (50N),
Setting Range Is 0.1 to 0.4 x Itheta Measured Earth (50G)
Operate Level 100% Is ± 5% or ± 1% x In Setting Range Is: -
IT Min. Operate Time 0 to 20s O/C ‘50’ 0.05 to 50 x In
DT Delay Setting td 0 to 20s Derived E/F ‘50N’ 0.05 to 50 x In
DT Basic Operate Time – Measured E/F ‘50G’ 0.005 to 5 x In
2 x Is 40ms ± 10ms Time Delay 0.00…14400s
5 x Is 30ms ± 10ms Operate Level 100% Is ± 5% or ± 1% x In
DT Operate time td ± 1% or ± 30ms Operate time
following delay. 2 x Is 35ms ± 10ms
Tm Time Multiplier 0.025 to 2.0 5 x Is 25ms ± 10ms
Overshoot Time < 40ms Operate time following tbasic +td , ±1% or ±10ms
Inhibited by Binary or Virtual Input delay
Inhibited by Binary or Virtual Input
Inrush detector
47 Negative Phase Sequence Voltage VT Supervision

Number of Elements 2
Setting Range Vs 1 to 90V
Hysteresis Setting 0 to 80%
Operate Level 100% Vs ± 2% or ± 0.5V
Delay Setting td 0 to 14400s
Basic Operate Time: -
2 x Vs 80ms ± 20ms
10 x Vs 55ms ± 20ms
Operate time following tbasic +td ± 2% or ± 20ms
delay.
Overshoot Time < 40ms
Inhibited by Binary or Virtual Input

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51 (67) Time Delayed OC&EF (Directional) 81 Under/Over Frequency

Operation Non directional, Forward or Number of Elements 2 Under or Over

reverse U/V Guard 35 to 200V
Elements Phase (51), Derived Earth (51N), Setting Range Fs 43 to 68Hz
Measured Earth (51G) Hysteresis Setting 0 to 2%
Characteristic IEC: NI,VI,EI,LTI Operate Level Fop 100% Fs ±10mHz
ANSI: MI,VI,EI Reset Level: -
DTL Under Frequency (100% + hyst) x Fop ± 10mHz
Setting Range Is 0.05 to 2.5 x In (OC, N) Overv Frequency (100% - hyst) x Fop ± 10mHz
0.005 to 0.5 x In (G) Delay Setting td 0 to 14400s
Time Multiplier 0.025 to 100 Basic Operate Time: -
(IEC/ANSI) For ROCOF between Typically < 110ms
Time Delay 0 to 20s 0.1 and 5Hz/second Maximum < 150ms
Operate Level 105% Is ± 4% or ± 1% x In Operate time tbasic +td ± 1% or ± 10ms
Minimum Operate time top
K
Tm following delay.
IEC I
Is 1 Inhibited by Binary or Virtual Input, Voltage
A Guard
top B Tm
ANSI I P
Is 1

5% or 30 ms 87REF Restricted Earth Fault

Follower Delay 0 - 20s
Reset ANSI decaying, 0 – 60s
Setting Range Is 0.005 to 2.0 x In
Inhibited by Binary or Virtual Input
Operate Level 100% Is ± 5% or ± 1% x In
Inrush detector
Time Delay 0 to 60s
Basic Operate Time
2 x Is 40ms ± 10ms
50BF Circuit Breaker Fail 5 x Is 30ms ± 10ms
Inhibited by Binary or Virtual Input
Operation Current check - Phase and
Measured Earth with
independent settings,
Mechanical Trip,
CB Faulty Monitor
Setting Range Is 0.05 to 2 x In (50BF)
0.005 to 2 x In (50BF-I4)
2 Stage Time Delays Timer 1: 0.02 to 60s
Timer 2: 0.02 to 60s
Operate Level 100% Is ± 5% or ± 1% x In
Basic Operate time < 20ms
Operate time following tdelay ±1% or ± 20ms
delay
Triggered by Any function mapped as trip
contact.
Inhibited by Binary/Virtual Input
Timer By pass Yes, 50BF CB Faulty Input

55 Power factor

Number of Elements 2
Operation Under or Over
U/C Guard 0.05 to 1.0
Setting Range PFs 0.05 to 0.99
Time Delays 0 to 14400s
Operate Level ± 0.05
Basic Operate time 70ms
Operate time following tbasic +td ± 1% or ± 10ms
delay
Inhibited by Motor not running, VTS

Siemens Protection Devices Limited 11

 Case Dimensions

Fig 4. Case overall dimensions and panel drilling details (All dimensions are in mm)

Siemens Protection Devices Limited 12

 7SR1702/3 Rho Connection Diagram (4CT)

+ve +ve
2 3
-ve BI 1 BI 4 -ve
4 1
+ve +ve
6 5
BI 2 BI 5
-ve
8
+ve +ve
10 7
-ve BI 3 BI 6 Optional
12

9
14 +ve
BO 6 11
16 GND
BO 7 13
18 -ve
BO 8 15
20 Term.

+ve
22
-ve
24

28 GND.

B
1A
13 3

14 BO 1 1
5A IA
15 2

16 4
1A
17 BO 2 6

18 5
5A IB
19

20
8
21
1A BO 3
7
22
5A IC 10
23 BO 4
9
24
1A 12
25 BO 5
11
26
5A IG
27

28
A

1 2 1 2
NOTES
BI = Binary Input,
BO = Binary Output

B A Shows contacts internal

to relay case assembly.
Contacts close when
relay chassis withdrawn
27 28 27 28
from case

Fig 5. 7SR1702/3 Rho Wiring Diagram

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 7SR1705/6 Rho Connection Diagram (4CT, 3VT)

+ve +ve
2 3
-ve BI 1 BI 4 -ve
4 1
+ve +ve
6 5
BI 2 BI 5
-ve
8
+ve +ve
10 7
-ve BI 3 BI 6 Optional
12

9
14 +ve
BO 6 11
16 GND RS485
BO 7 13
18 -ve
BO 8 15
20 Term.

17

19
+ve
22 See
Relay 21
-ve
24 Voltage
Config. 23
Setting
28 GND. 25

B 27

1A
13 3

14 BO 1 1
5A IA
15 2

16 4
1A
17 BO 2 6

18 5
5A IB
19

20
8
21
1A BO 3
7
22
5A IC 10
23 BO 4
9
24
1A 12
25 BO 5
11
26
5A IG
27

28
A

1 2 1 2

NOTES
BI = Binary Input, BO = Binary Output

B A Shows contacts internal

to relay case assembly.
Contacts close when
relay chassis withdrawn
27 28 27 28
from case

Fig 6. 7SR1705/6 Rho Wiring Diagram

Siemens Protection Devices Limited 14

 7SR17 Rho Function Diagram

Fig 7. 7SR1702/3 Rho Function Diagram

Fig 8. 7SR1705/6 Rho Function Diagram

Siemens Protection Devices Limited 15

 Ordering Information – 7SR17 Rho Motor Protection Relay

RHO 7 S R 1 7 0 - A 1 2 - A 0
Motor Protection | | | | | | | | | |
Protection Product / Type | | | | | | | | | |
Motor thermal 7 0 | | | | | | | |
| | | | | | | |
Case I/O and Fascia 1) | | | | | | | |
E4 case, 4 CT, 3 BI, 5 BO, 10 LEDs 2 3 | | | | | |
E4 case, 4 CT, 6 BI, 8 BO, 10 LEDs 3 3 | | | | | |
E4 case, 4 CT, 3 VT, 3 BI, 5 BO, 10 LEDs 5 4 | | | | | |
E4 case, 4 CT, 3 VT, 6 BI, 8 BO, 10 LEDs 6 4 | | | | | |
| | | | | | |
Measuring Input | | | | | | |
1/5 A, 50/60Hz with SEF input 2/3 3 | | | | | |
1/5 A, 40 – 160V, 50/60Hz with SEF input 5/6 4 | | | | | |
| | | | | |
Auxiliary voltage | | | | | |
80 to 250V DC / 115V AC, binary input threshold 19V DC G | | | | |
80 to 250V DC, binary input threshold 88V DC H | | | | |
24 to 60V DC, binary input threshold 19V DC J | | | | |
| | | | |
Communication Interface | | | | |
Standard version – included in all models, USB front port, RS485 rear port 1 | | | |
| | | |
Protocol | | | |
IEC 60870-5-103, Modbus RTU, DNP3.0 or Modbus RTD Client (user selectable setting) 2 | | |
| | |
Front Cover | | |
Standard version – No Push Buttons 1 | |
Push Buttons – Down and Right arrows 2 | |
| |
Protection Function Packages | |
Standard version – Included in all models C |
14 Stall Protection |
37 Undercurrent |
46 Phase Unbalance Protection |
46PhRev Phase Reversal |
48/66 Start Protection |
49 Thermal Overload |
49RTD Interface: RTD monitoring via comms |
50/51 Overcurrent |
50/51, GN Earth fault |
50BCL Break Capacity Limit |
50BF Circuit breaker fail |
60CTS-I CT Supervision |
74T/CCS Trip/Close circuit supervision |
81B Anti Backspin |
87REF High Impedance Restricted Earth Fault |
Programmable logic |
|
For variants with 3 x VT inputs as above - plus |
27/59 Under/Over Voltage |
32/55 Directional Power/Power Factor |
47 NPS Overvoltage/Phase Reversal |
60CTS Enhanced CT Supervision |
60VTS VT Supervision |
67/50, 67/51 Directional Overcurrent |
67G/N Directional Earth Fault |
81 Frequency |
|
Additional Functionality |
No Additional Functionality A
1) BI = Binary input, BO = Binary output

Siemens Protection Devices Limited 16

Siemens Protection Devices Limited 17
Siemens Protection Devices Limited 18
Siemens Protection Devices Limited 19
 Siemens Protection Devices Limited
P.O. Box 8
North Farm Road
Hebburn
Tyne & Wear
NE31 1TZ
United Kingdom
Phone: +44 (0)191 401 7901
Fax: +44 (0)191 401 5575
E-mail: marketing.spdl.gb@siemens.com

SPDL-C051-3

For enquires please contact our Customer Support Center

Phone: +49 180/524 8437 (24hrs)
Fax: +49 180/524 24 71
E-mail: support.energy@siemens.com
www.siemens.com/protection

Subject to change without notice,. Printed in the UK.

www. siemens.com/energy

Siemens Protection Devices Limited 20