E1/T1 PCI card installation guide
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Speech Calls
If the E1/T1 PCI card is used in an application that makes or answers calls with a service code
that indicates a speech or telephony call, or any call that may use a partly analogue route, there
is a requirement that audio signals transmitted are encoded using CCITT A-law PCM, and do not
exceed a 1 minute mean power level of -9dBm.
Many of the speech and FAX resource cards that may be used with the E1/T1 PCI card comply
with this requirement. It is the responsibility of the user to ensure that this requirement is
complied with, by confirmation via the manufacturer of the card, or by any other suitable means
such as independent testing.
Signal sources that do not guarantee compliance with this requirement must be conditioned by
appropriate circuitry before transmission.
Card Installation & Connection
Safety Warnings
Interconnection circuits should be such that the equipment continues to comply with the
requirements of 2.3 of EN 60950 for SELV circuits, after making connections between circuits
using any of the internal ports.
The host system into which the E1/T1 PCI card is fitted is classed as an indirect attachment. The
PCI bus connector provides an interconnection circuit between the host system and the E1/T1
PCI card. Similarly, equipment connected to the E1/T1 PCI card H.100 CTBus ports are also
classed as indirect attachments.
Installation and Safety
The card must be installed such that, with the exception of the PCI, H.100 bus connections,
clearance and creepage distances shown in the table below are maintained between the E1/T1
PCI card and any parts of the host system or other expansion cards which use or generate a
voltage, shown in the following table below.
Clearance mm
Creepage mm
Voltage present on other parts of
the host or on expansion cards.
2.0
2.4 (3.8)
Up to 50V rms or dc
2.6
3.0 (4.8)
Up to 125V rms or dc
4.0
5.0 (8.0)
Up to 250V rms or dc
4.0
6.4 (10.0)
Up to 300V rms or dc
WARNING
ADVICE FROM A COMPETENT TELECOMMUNICATIONS SAFETY ENGINEER MUST BE OBTAINED BEFORE INSTALLATION OF THE RELEVANT
EQUIPMENT USING OR GENERATING VOLTAGES GREATER THAN 300V (RMS OR DC).
Clearance distances refer to the shortest distance between parts, measured through air. Creepage
distances refer to total distances measured across surfaces when installed in a normal office
environment. The creepage distances in parenthesis apply where the local environment within
the PC is subject to conductive pollution or dry non-conductive pollution that could become
conductive due to condensation.
If in doubt seek advice from a competent telecommunications safety engineer.
In order to maintain the host independent approval of the E1/T1 PCI card, it is essential that,
when other expansion cards are introduced which use or generate a hazardous voltage, the
minimum creepage and clearances specified above are also maintained. A hazardous voltage is
one that exceeds 42.4V ac peak or 60V dc. If you have any doubt, seek advice from a competent
engineer before installing other adapters into the host equipment.
Failure to install the E1/T1 PCI card in accordance with these instructions will invalidate the
Approval.