IBM Nways 8260, Installation Manual

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Setting the Grounding Jumpers
E1 and T1/J1 Twisted-Pair Connections
Twisted-pair connections should not be grounded. You must remove the grounding
jumpers from both the Transmit and the Receive jumper pins for each port that has a
twisted-pair connection.
E1 Coaxial Connections
Regulations governing the grounding of outer conductors on E1 coaxial pairs vary from
country to country. To conform to these country-specific regulations, eight jumpers
(one for Transmit and one for Receive on each port) are provided on the rear of the
E1/T1/J1 and E1/T1/J1 IMA I/O cards (see Figure 1 on page 6 and Figure 2 on
page 7)
Ÿ
If a jumper is inserted over a pair of jumper pins, the outer connector of the
corresponding port is grounded to the Frame Ground.
Ÿ
If no jumper is inserted, the outer connector of that port is grounded through a 10
nF capacitor.
Normally, only the outer connector of the transmit port is to be grounded, and not the
receive port. This depends on individual country regulations. Check to see whether
your country also requires the receive port to be grounded.
Note: Standard G.703 recommends that the outer conductor of the coaxial pair be
connected to ground on the transmit port, and that the same provision be available for
the receive port. Some countries however, have different rules, so the setting may be
not apply.
Table 2. Ground Jumper Settings for E1 Coaxial Connections
To Ground Outer of: Place Jumper On: To Ground Outer
of: Place Jumper On:
Port 1 Receive JP9 Port 3 Receive JP13
Port 1 Transmit JP10 Port 3 Transmit JP14
Port 2 Receive JP11 Port 4 Receive JP15
Port 2 Transmit JP12 Port 4 Transmit JP16
Chapter 3. Installing an E1/T1/J1 or E1/T1/J1 IMA I/O Card
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