Introduction—Surge Protection Devices

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

unlimited Amps in parallel

• Suitable for AC or DC application

• Thermal and short circuit protection

• LED status indication feature

• 10 year product warranty

SD Series

SLP Series

Data and Signal Protection

The SD Series are ultra-slim user-friendly devices for protecting

electronic equipment and systems against surges on signal

• 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

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 field-mounted 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:

Introduction—Surge Protection Devices

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.

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

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.

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.

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.

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

The individual fuse module prevents a fault or follow on

current on one loop disrupting the power supply to the

maintenance or added without requiring additional disconnect

terminals.

The following guide provides application information for the

SD series. For technical information, see page 84.

Surge Protection Devices—SD Series

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

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.

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,

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.

Surge Protection Devices—SD Series

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

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.

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.

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.

The recommended grounding for field-mounted devices has

been illustrated previously. The grounding at the control panel

In all installations utilizing safety related apparatus, consideration

should be given to protecting the system supply and any long

communication cable.

Surge Protection Devices—SD Series

All figures typical at 77°F (25°C)

unless otherwise stated

Full hybrid line to line

Each line to screen/ground

Max. discharge surge current (Imax) (8/20µs)

10kA (8/20μs)

Response time

RTD resistance range (SDRTD)

10 to 1500Ω

Degradation accuracy (SDRTD at 1mA)

0.1% (RTD resistance > 100)

0.1W (RTD resistance < 100)

Ambient temperature

–40°C to +80°C - working (-40°F to 176°F)

–40°C to +80°C - storage (-40°F to 176°F)

9kA (SD150X and SD275X only)

Impulse durability (8/20µs)

6.5kA (SD150X and SD275X only)

T-section DIN-rail 35 x 7.5 or 35 x 15mm rail

(1.38” x 0.3” x 0.6”)

80kPa - 160kPa

5% - 95% RH

EMC compliance

To Generic Immunity Standards,

EN 50082, part 2 for industrial

R&TTE compliance

EN 50082-2 : 1995

EN 41003 : 1999

EN 60950 : 1992

EN 41003 : 1999

IEC compliance

EN 61643-21:2001

Ordering Data

Technical Data

Part No.

Part No.

Ordering Data

Technical Data

Part No.

Part No.

Part No.

Part No.

Part No.

Mounting Accessories

Allen Bradley Data Highway Plus SD16R

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

Application Part No. Part No.

PROFIBUS

DP SD32R

PA (IEC 1158, 31.25 kbits/s) SD32R

RS232 SD16 SD16X

RS422 SD07R

RS423 SD07R

RS485 SD07R

WorldRP (IEC 1158) SD32R