Datasheet
Surge Protection Devices
SD Series Data and Signal
SLP Series Data and Signal
MA15 Series AC and DC Power
TP48 Series Transmitter and Sensor
Protection
Protection
Protection
Protection
SD Series
SLP Series
Data and Signal Protection
NEW
The SD Series are ultra-slim user-friendly devices for protecting electronic
equipment and systems against surges on signal and I/O cabling, and
the SLP Series provides 20kA power surge protection for process
control, equipment systems and distribution panels.
Product Features:
• Range of ATEX Certified intrinsically safe surge protectors
• Ultra-slim and space saving designs; easy installation
• Multistage hybrid protection circuitry - 10kA maximum surge current
for SD Series, and 20kA maximum surge current for SLP Series
• Range of voltage ratings ideal for process I/O applications
• Designed for high bandwidth, low resistance applications; RTD,
Public Switch Telephone Network (PSTN) and 3-wire transmitter
versions available in SD Series
• Surge protection for two loops or one 4-wire circuit per
SLP Series module
• 10 year product warranty
MA15 Series
AC & DC Power Protection
The MA15 Series of surge protection devices protects electronic
equipment and computer networks against the effects of noise
pollution induced in power supplies. MA15 units filter out and
suppress the effects of industrial noise and surges caused by
lightning, switching devices, thyristor controls, transmission system
overloads and power-factor correction circuits.
Product Features:
• 18kA surge protection and RFI filtering
• Protects panel loads up to 15 Amps in series,
unlimited Amps in parallel
• Suitable for AC or DC application
• Thermal and short circuit protection
• LED status indication feature
• 10 year product warranty
The SD and SLP Series surge protection devices provide unparalleled
packing densities, application versatility, proven and reliable hybrid
circuitry, simple installation and optional ‘loop disconnect’ facilities (SD
Series). These features make the SD and SLP Series the ultimate surge
protection solutions for process control equipment, I/O systems and
communications networks.
TP48 Series
Transmitter and Sensor Protection
The TP48 Series of transmitter protectors safeguards electronic process
transmitters against induced surges and transients from field cabling.
They uniquely provide a level of protection for 2, 3 and 4 wire fieldmounted transmitters that greatly exceeds the optional transient
protection facilities available from the transmitter manufacturers without
any additional wiring, conduit modifications or other expensive extras.
Product Features:
• Easy and direct mounting – simply screw into spare conduit entry
• Intrinsically safe; flameproof to CENELEC standards; ATEX approved
• Parallel connection avoids introduction of resistance into loop
Canada
Mexico
United States
Weidmuller, Canada
10 Spy Court
Markham, Ontario L3R 5H6
Telephone: (800) 268-4080
Facsimile: (905) 475-2798
Email: info1@weidmuller.ca
Website: www.weidmuller.ca
Weidmuller, Mexico
Blvd. Hermanos Serdán 698
Col. San Rafael Oriente
Puebla, Puebla, Mexico
C.P. 72029
Telephone: 01 222 2686267
Facsimile: 01 222 2686219
Email: clientes@weidmuller.com.mx
Website: www.weidmuller.com.mx
Weidmuller
821 Southlake Blvd.
Richmond, Virginia 23236
Telephone: (800) 849-9343
Facsimile: (804) 379-2593
Email: info@weidmuller.com
Website: www.weidmuller.com
Surge Protection Devices
SD Series
SLP Series
The exceptionally high packing densities are the result
of an ultra slim footprint for individual modules, which
can double-up as feedback terminals. Each module
provides full hybrid surge protection for 2 and 3-wire
loop protection.
The multi-stage hybrid surge protection network at the
heart of the SLP uses a combination of solid state electronics
and a gas filled discharge tube (GDT) to provide surge
protection up to 20kA. This impressive surge protection
circuit is designed to exhibit exceptionally low line resistance
and adds only a minimal voltage drop to the circuit.
Modules with a comprehensive range of voltage ratings
cover all process related signals such as RTDs, Thermocouples (THCs), 4 - 20mA loops, telemetry outstations,
shut-down systems and fire and gas detectors.
The optional loop disconnect featured on the SD07, SD16,
SD32 and SD55 modules allows users to perform
commissioning and maintenance without removing the
surge protection device. In addition, a third connection
on the field and safe side of the module is provided for
safe termination of shields.
For three wire applications the specially designed
SDRTD (Resistance Temperature Detector) and the
SD32T3, (for separately powered 4 - 20mA loops)
provide full 3-wire protection in a single compact unit.
The SD07R3 provides protection of 3-wire pressure
transducers on low power circuits.
For higher bandwidth applications, the SDR Series
meets the demands of today’s highest speed
communication systems.
120V and 240V AC versions are available for I/O and
power supplies up to three Amps of load current.
Telephone networks can be protected by the SDPSTN.
All modules are DIN-rail mountable on a TS-35 rail.
A comprehensive range of mounting and grounding
accessories are available.
2
The SLP device does not adversely affect the performance
or operation of the loop or combined equipment during
operation. The device allows signals to pass with very little
attenuation, while diverting surge currents safely to the
ground and clamping output voltages to safe levels.
Fully automatic in operation, SLP devices react immediately
to ensure that equipment is never exposed to damaging
surges between lines or the lines and ground. Reacting
instantly, the SLP redirects surges safely to the ground
and resets automatically.
The versatile SLP series provides full hybrid surge
protection, combining protection for two process
loops into one case.
For higher bandwidth applications, the SLP series has been
developed to meet the demands of today’s highest speed
communication systems.
SD Series
Surge Protection Devices
SD Series Guide to applications and selection
The SD Series of signal protection devices includes models for a full range of applications operating at voltages up to
250V ac. The optional fuse/disconnect package provides both fused protection against fault currents and a convenient
method of isolating field circuitry from protected circuitry without requiring additional disconnect terminals. The standard
fuse (replaceable) is rated 250mA. 50mA fuses are available by special request. Solid links can be used in applications
where only the disconnect feature is required.
This feature is important in applications where a signal protection device is used with a bulk power supply feeding multiple
loops. The individual fuse module prevents a fault or follow on current on one loop disrupting the power supply
to the others. In addition, loops can be removed from the circuit for maintenance or added without requiring additional
disconnect terminals.
The following guide provides application information for the SD series. For technical information, see page 9.
Analog inputs (high-level)
2-wire transmitters, 4-20mA, conventional and smart
SD32 and SD55 are recommended for use with
conventional and smart 4-20mA transmitters (fed by a
well-regulated supply), the choice dependent upon the
maximum working voltage of the system (32V and 55V
respectively). The diagram illustrates an application using
the fuse/disconnect. Both models are available in ‘X’
versions without the optional fuse/disconnect feature.
PROTECTED CIRCUIT
FIELD CIRCUIT
Bulk
PSU
1 Up to 50V dc
4/20mA
1 to 5V
2
4
TP48
transmitter
protector
5
6
3
SD32
SD55
SD32X
SD55X
(no fuse)
Multiple
Loops
2-wire transmitters
SDRTD
1
4
5
Analog inputs (low-level)
RTDs, Thermocouples (THCs) and mV sources
using the SDRTD.
For optimum accuracy, the energizing current should be
chosen to ensure the voltage across the RTD does not
exceed 1V over the full measurement range. When using
a PT100 device, an energizing current of 1mA is
recommended.
Recorder
Controller
Computer
etc.
2
6
3
SDRTD
3-wire RTDs
2xSD07X
or 2xSD16X
1
4
Photocell
Thermocouple (THC)
Signal
5
mV source
2
Turbine
Flowmeter
6
3
SD07
SD16
SD07X
SD16X
(no fuse)
Photocells and turbine flowmeters
Depending upon the operational voltage, the SD07
or SD16 are the preferred choices for this application.
SD07X and SD16X are also suitable.
photocells,
thermocouples (THCs),
mV sources and
turbine flowmeters
3
Surge Protection Devices
Analog outputs
Controller outputs (I/P converters)
Dependent on the working voltage, recommendations
include the SD16, SD32 and SD55, and the equivalent
‘X’ versions.
SD Series
PROTECTED CIRCUIT
FIELD CIRCUIT
2xSD15X, SD32X
1
4
P
V
I
5
2
6
OV
3
SD16
SD32
SD35
SD16
SD32X
SD55X
(no fuse)
Controller outputs
(I/P converters)
Digital (on/off) inputs - Switches
Suitable signal protection devices include the SD07, SD16,
SD32 and SD55 modules, and the equivalent “X” versions.
The choice is dependent upon the operating voltage of the
system.
SD
1
4
5
V
2
6
Logic Signal
3
SD07
SD16
SD32
SD55
SD07X
SD16X
SD32X
SD55X
OV
(no fuse)
Switches
SD32X
1
4
Digital (on/off) outputs Alarms, LEDs, solenoid valves, etc.
The SD32 or SD32X are the recommended choice for this
application.
LED
Alarm
5
32V max
2
6
3
SD32
SD32X
(no fuse)
Alarms, LEDs, solenoid
values, etc.
4
Incoming
Telephone
Line
Telemetry Public Switch Telephone Network
(PSTN) - Telemetry outstations
The SDPSTN has been designed specifically for the
protection of signals transmitted on public switched
telephone networks.
5
3
Telecom line
4
5
6
4
Modem,
fax or
telephone
2
6
110/120V ac
or
220/240V ac
AC supplied equipment - PLC, I/O systems
The recommended choice or systems on 110-120V ac is
the SD150X ; for 220-240V ac systems, the SD275X is
recommended.
1
PLC, I/O systems
Final output from
1
PLC,
DCS,
SCADA,
etc.
2
3
SD Series
Surge Protection Devices
Transmitter and sensor protection
Transmitters and sensors are widely used in highly exposed areas and where lightning damage is common. In many
cases, the ideal solution for 2-wire transmitters or sensors is the TP48, which mounts directly onto the transmitter via
spare conduit entries or a tee fitting. Where these entries are not available or 3-wire devices are used, the compact
design and simple installation of the SD Series makes it an ideal choice for transmitter protection.
The SDs within the junction box should be installed as close as possible to the sensor or transmitter they are protecting,
but no further than one meter away. A bond is required from the general mass of steelwork to the sensor or transmitter
housing, using either a flat short braid or a cable at least 0.16 inch2 (4mm2) cross sectional area. In most instances, this
bond is made automatically by fixing the metallic transmitter housing to the plant structure and ensures the voltage
difference between the signal conductors and the transmitter housing is below the transmitter’s insulation rating.
Please note that the transmitters or sensors are connected to the SD protected equipment terminals, not the field cables.
2-wire transmitters or sensors
4-20mA transmitters - conventional and smart
The SD16X, SD32X and SD55X are an excellent alternative
if the TP48 is not an acceptable solution, either because of
technical suitability or mounting difficulties.
TO HOST CIRCUIT
SD PROTECTED FIELD CIRCUIT
1
4
4-20mA
2
5
6
3
Plant structure
3-wire transmitters or sensors
Vibration Sensors and 4-20mA loop process control
systems generally require three wire connections when
powered from an external source. This may be
accomplished in one unit by using the SD32T3 3- terminal
Surge Protection Device (SPD). Because the SD32T3
protects all three conductors within the same unit, higher
protection is achieved because the SPD hybrid circuitry is
common to all three wires.
The SD07R3, SD16R3, SD32R3 and SD55R3 are also
suitable for the protection of 3-wire pressure transducers
on low power circuits.
SD16X
SD32X
SD55X
SPD DIN rail
2-wire transmitter or sensor
4
1
2
Plant structure
24V
5
3
4-20mA
6
Common OV
SD32T3
SPD DIN rail
3-wire transmitter or sensor
1
4
4-20mA
2
4-wire transmitters or sensors Flow meters, level detectors, etc.
4-wire systems such as level detectors require two SDs,
one for the supply and the other for the transmitter output.
Generally the voltages across the pairs are similar, so the
recommended choice is a pair of SD16X, SD32X or
SD55Xs. Dependent upon the supply voltage, AC powered
transmitters should be protected with an SD150X for the
supply inputs.
5
6
3
1
4
Supply voltage
Plant structure
2
5
Supply OV
6
3
SD16X
SD32X
SD55X
SPD DIN rail
4-wire transmitter or sensor
5
Surge Protection Devices
SD Series
Communication systems protection
High-speed data links between buildings or one part of a plant to another have become more common with the
widespread use of smart transmitters and the increase in remote installations. The SD Series has an SPD suitable for
all process I/O applications with a choice of low resistance units, high bandwidth and a variety of voltage ranges.
Featuring an extremely high bandwidth, the SDR Series is designed to meet the requirements for high speed data links.
Communication systems
RS232, RS422, RS485
The recommended choice for these applications is the
SD16R or SD32R depending on the maximum driver signal.
SD PROTECTED HOST CIRCUIT
TP PROTECTED
FIELD CIRCUIT
4
TP48
1
5
2
6
3
RS232, RS422, RS485
Bus powered systems
There are a variety of bus powered systems specially
designed for the process industry. The ideal surge
protection device for these systems is the SD32R, with
a very high bandwidth and modest in-line resistance.
SD PROTECTED HOST CIRCUIT
PROTECTED FIELD CIRCUIT
1
4
4
5
2
6
3
1
5
2
6
SD32R
(no fuse)
3
SD32R
(no fuse)
TP48
4
5
6
1
2
3
SD32R
(no fuse)
Bus powered systems
Typical Applications
Table 1 shows suitable SD devices for different applications.
In some applications alternative devices may be used, for
example, where lower in-line resistance or a higher voltage
power supply is used.
MTL Surge Technologies has operationally tested the
recommended SD Series units with the representative
highways listed. However, no formal approval for their
use in these systems has been sought from the
respective bodies.
Table 1
Application
Preferred Part No.
Allen Bradley Data Highway Plus
SD16R
Alternate Part No.
Foundation Fieldbus
31.25kbits/s voltage mode
SD32R
1.0/2.5 Mbits/s
SD55R
HART
SD32X
SD32, SD32R
Honeywell DE
SD32X
SD32, SD32R
LonWorks
FFT-10
SD32R
LPT-10
SD55R
TP-78
SD07R
IS78†
SD32R
Modbus & Modbus Plus (RS485)
SD16R
PROFIBUS
DP
PA (IEC 1158, 31.25 kbits/s)
SD32R
SD32R
RS232
SD16
RS422
SD07R
RS423
SD07R
RS485
SD07R
WorldRP (IEC 1158)
SD32R
31.25 kbits/s voltage mode
1.0/2.5 Mbits/s
6
SD55R
SD16X
SD Series
Hazardous area applications
Zone0/Zone1
The dangers from lightning induced sparking in Zone 0 are
considered real enough to require preventative measures.
IEC 60079-14 (1996-12) Electrical apparatus for explosive
gas atmospheres Part 14: Electrical installations in
hazardous areas (other than mines) stresses the
importance of SPDs in hazardous areas. An outdoor
installation where there is a high likelihood of both lightning
induced transients and combustible gases requires the
installation of SPDs to prevent possible ignition of the
gases. Areas seen particularly at risk include flammable
liquid storage tanks, effluent treatment plants, distillation
columns in petrochemical works and gas pipelines.
SPDs for transmitter protection should be installed in Zone 1,
sufficiently close to the Zone 0 boundary to prevent high
voltages entering Zone 0. The distance from the SPD to
Zone 0 should be less than 36” where possible. In practice
the SPD would normally be mounted on the transmitter or
sensor housing which usually lies in Zone 1 and is very
close to Zone 0. Because there is only a very small free
volume, the SD series is suitable for mounting in flameproof
or explosion proof enclosures.
Zone 2
The SD series is suitable for protecting electrical circuits in
Division 2, Zone 2 and can be used without affecting the
safety aspects of the circuit. Non-incendive (low-current)
circuits can be protected using any SD series unit mounted
in either the safe or hazardous area, including those with the
fuse disconnects facility. Nonarcing (high current) circuits can
also be protected, however SPDs with the fuse disconnect
facility may only be mounted in the safe area. For use in
these circuits the units must be mounted in a suitable
enclosure. In most cases the minimum requirements are
IP54 and 7Nm resistance to impact. The SD series is self
certified by MTL Surge Technologies as suitable for this
purpose.
Certification
Introducing surge protection into Intrinsically Safe (IS)
circuits is trouble free as long as the current and power
parameters are not exceeded. In the SD series, the SD**X,
SD**R, SD**R3, SDRTD and SD**T3 all have ATEX
certification for use in IS circuits located in Zones 0, 1 or 2.
The certification parameters for the SD**X and SD**T3 are:
EEx ia IIC T4, Li = 0.22mH
li = 260mA for Ui up to 20V
li = 175mA for Ui up to 26V
li = 140mA for Ui up to 28V
li = 65mA for Ui up to 60V
Surge Protection Devices
The certification parameters for the SD**R, SD**R3
and SDRTD are:
EEx ia IIC T4, Li = 0
li = 260mA for Ui up to 60V
The power rating for each of the above is dependent on the
table shown below.
Pi = 1W (–30°C to +75°C)
Pi = 1.2W (–30°C to +60°C)
Pi = 1.3W (–30°C to +40°C)
The SD** series are classified as simple apparatus and are
intended for use in Zone 2 or safe areas only, because their
fuses are not fully encapsulated.
Installation
Positioning
The SDs should be mounted on the field wiring side to ensure
that any surges entering from the field do not damage any
intrinsically safe barriers or galvanic isolators in the system.
The SDs and intrinisically safe interface should be mounted
close to each other but on separate DIN-rails in order to
maintain the required 1.97” (50mm) clearance between safe
area and hazardous area terminals of the IS interface.
SD series DIN rail
IS barrier DIN rail
Instrument
Field cables
Instrument earth
Substation ground mat
Grounding
The recommended grounding for field-mounted devices has
been illustrated previously. The grounding at the control panel
is more critical as there are usually a number of grounding
systems, each with their own requirements.The grounding
system illustrated here replaces the instrument 0V bond, the
control system PSU bond and the IS ground with one single
ground connection to meet all the design requirements and
give the most effective protection against the effects of
lightning induced surges.
System Connection Cable
Marshalling cabinet
SPD
Isolated instrument rail
Isolated instrument rail
Electrical earth
Frame
connection
Floor void
System earth
To plant/neutral
star point
In all installations utilizing safety related apparatus,
consideration should be given to protecting the system supply
and any long communication cable.
7
Surge Protection Devices
Specifications SD Series
All figures typical at 77°F (25°C)
unless otherwise stated
Approvals
Standard
Certificate/File No.
Approved for
Product
Canada, USA
(CSA/C/US)
Country (Authority)
CSA C22.2 No. 0-M1991
CSA C22.2 No. 157-M1992
UL 913, 5th edition
CSA C22.2 No. 142-M1987
CSA C22.2 No. 213-M1987
UL 508, 17th edition
UL 1604, 3rd edition
LR 103652-3
EEx ia Class 1,
Groups A, B
C and D, T4
Class 1, Div 2
Groups A,B,C, D T4
SD07,SD16,SD32,SD55,
SD07X,SD16X,SD32X,
SD55X,SD07R,SD16R,
SD32R,SD55R,SDRDT,
SD32T3,SD07R3,SD16R3,
SD32R3,SD55R3
USA
(UL)
UL 497B Listed
E220693
Isolated loop
communication
circuits
SD07,SD16,SD32,SD55
SD07X,SD16X,SD32X
SD55X,SD07R,SD16R
SD32R,SD55R,SD07R3
SD16R3,SD32R3,SD55R3
SD32T3,SD55T3,
SD07X3,SD16X3,SD32X3,
SD55X3,SDRTD
USA, Canada
(UL)
UL 1449
Recognized Component
E217523
AC power
protection
SD150X,SD275X
Protection
Full hybrid line to line
Each line to screen/ground
Max. discharge surge current (Imax) (8/20µs)
10kA (8/20µs)
6.5kA (SD150X and SD275X only)
SD Series
Max. discharge surge current (isn)
3kA (8/20µs)
Lightning impulse current (Iimp) (10/350µs)
2.5kA
1.0kA (SD150X and SD275X only)
Response time
100 )
0.1W (RTD resistance < 100 )
3.9”
(99mm)
Ordering Data
Part No.
Part No.
Part No.
Part No.
SD07
SD16
SD32
SD55
Nominal voltage+(Un) Vdc
7
16
32
55
Nominal voltage+(Un) Vac
5
11
22
38
Nominal current (In) mA
250
250
250
250
Series resistance W/line
4.2
4.2
4.2
4.2
Max. leakage current µA
500
5
5
5
Rated voltage (MCOV) Uc
Voltage protection level (Up)
7.7
17
36
62