Echelon LonWorks Router User Manual

Page 85

Table 17. Bill of Materials for the FT Router 5000 and FT-X3 Interconnection

Designator

Value

Description

4.99 kΩ

Pullup resistor

VR1

470 V MOV, 5 mm, 40 pF (typical)

Panasonic ERZV05D471, Digi-Key

P7186-ND or equivalent

C1, C2

56 pF, 50 V

Common-mode noise immunity

capacitors (for EN61000-4-6 Level

C3, C4

100 pF, 5%

Optional center-tap capacitors

C5, C6

22 μF, ≥50 V, polar

DC blocking capacitors

D1, D2

BAV99

ESD transient clamping diodes

D3, D4, D5, D6

BAV99, 1N4148-equivalent
1N4934, 1N4935, FR1D, RS1D,

RS1DB

Differential network clamping

diodes:

For up to 2 kV Surge Protection
For up to 6 kV Surge Protection

In Figure 38, diodes D1 and D2 are ESD transient clamping diodes. Capacitors

C1 and C2 provide common-mode noise immunity for compliance with EN61000-

4-6 Level 3. Capacitors C5 and C6 are used to provide DC voltage isolation for

the FT 5000 Smart Transceiver when it is used on a link power network and to

protect it in the event of a DC power fault on the network wires. The capacitors

are required to meet L

ARK

interoperability guidelines for the TP/FT-10

channel. These capacitors are not needed for devices that will be connected

exclusively to non-link power networks and do not require protection against DC

faults. Two polar capacitors are used to protect against the application of a DC

voltage of either polarity, while providing a total capacitance of 11 μF.

Alternatively, a single non-polar capacitor of 10 μF can be used in either of the

two legs that connect to the network. The initial tolerance of the capacitor should

be ±20% or less, and degradation due to aging and temperature effects should not

exceed 20% of the initial minimum value.
In some cases, adding capacitors (C3 and C4) between the center tap pins of the

FT-X3 Communications Transformer and ground can reduce EMI emissions. If

used, C3 should always be connected to logic ground. If used, C4 can connect to

either logic ground or Earth ground, depending on whether your device connects

Earth and logic ground.
See the Series 5000 Chip Data Book for information about connecting a Series

5000 chip to a TP/FT-10 channel, including the FT Router 5000, and for

information about the FT-X3 Communications Transformer.

ORKS

Router User’s Guide