Westermo ODW-641 User Manual

Page 13

6650-2291

Optical Power Budget
The maximum supported link lengths as specified in the table above should only been
seen as indicative. The allowed link length is calculated from the Optical Power Budget
(OPB), (the available optical power for a fibre-optic link), and the attenuation of the fibre,
comprising losses due to in-line connectors, splices, optical switches and a margin for link
aging (typical 1.5 dB for 1300 nm).
The worst-case Optical Power Budget (OPB) in dB for a fibre-optic link is determined
by the difference between the minimum transmitter output optical power and the lowest
receiver sensitivity.

Output power is power coupled into a 62.5/125 μm multimode fibre.

** Output power is power coupled into a 9/125 μm singlemode fibre.

*** The optical power should be reduced by at least 5 dB (SM-LC80)

or 3dB (SM-LC80) between the optical output and input.

FX (Fibre)

SM-LC80 SM-LC40 SM-LC15

MM-LC2

Fibre connector

LC duplex

Fibre type

Singlemode

9/125 μm

Singlemode

9/125 μm

Singlemode

9/125 μm

Multimode

62.5/125 and

50/125 μm

Wavelength

1550 nm

1310 nm

Transmitter
Output optical power min/max

–5/0 dBm

–15/–8 dBm

–20/–14 dBm

Receiver
Input sensitivity

–34 dBm

(max)

–34 dBm

(max)

–31 dBm

(max)

–31 dBm

(max)

Receiver
Input optical power Maximum

–5 dBm

(min) ***

–3 dBm

(min) ***

–8 dBm

(min)

–8 dBm

(min)

Optical power budget, worst case

29 dB

16 dB

11 dB

Bit error rate (BER)

<1 x 10

–10

<1 x 10

–10

<1 x 10

–10

<2.5 x 10

–10

Transceiver type

Small Form Factor Pluggable (SFP)
Multi-Sourcing Agreement (MSA) compliant

Laser class

Class 1, IEC 825-1 Accessible Emission Limit (AEL)

PROFIBUS DP (RS-485)

Electrical specification

EIA RS-485 / EN 50 170

Data rate

9 600 bit/s, 19.2, 93.75, 187.5, 500 kbit/s, 1.5, 3, 6 and 12 Mbit/s

Data format

8 data bits, even parity, 1 stop bit, 11 bits total

Protocol

PROFIBUS DP / EN 50170

Data Rate detection

Yes, compliant with EN 50 170

Retiming

Yes

Turn around time

In accordance with EN 50 170

Transmission range

≤ 1200 m, depending on data rate and cable type (EIA RS-485)

Settings

None, external termination and failsafe biasing

Protection

Installation Fault Tolerant (up to ±60 V)

Isolation to

Power and Status port

Connection

9-pin D-sub female

Shielded cable

Not required

Conductive housing

Isolated to all other circuits and housings