Nortel Passport 15000, Hardware Installation And Maintenance, Page: 860 / 874

860 Chapter 17 Hardware procedures
241-1501-240 5.2S2
Testing the power to the BIP
Test the input power to the BIP from each feed to confirm appropriate levels
of power to run the Passport 15000 or 20000 and to prevent inadvertent
damage to the cards before powering up the BIP.
Prerequisites
• You must be familiar with “Safety considerations and best practices”
(page 53).
• You need an accurate multi-meter with about 25-cm (10-in.) probes
(leads) as the specialty tool. A digital read-out is recommended as easier
to read.
• When a polyvalent or the ETSI power-and-ground assembly has been
installed, do the testing procedure at the terminal block clamping screws
that retain the power input cables. This test confirms connectivity and the
correct polarity of the power input cables to the terminal blocks. Then
repeat the testing procedure at the BIP studs.
• You must ensure the power to the unit is turned off before starting this
procedure.
Procedure steps
1 Facing the front of the BIP, ensure all of the breakers are off (O is pushed
in).
2 Verify there is no potential difference at the rear of the BIP using a
voltmeter as follows: Place the positive lead of the meter on the A1+ stud
and the negative lead of the meter on the A1- stud. A correct hookup
shows 0.0 volts. Repeat this step for the A2, B1, and B2 feeds.
3 Using an ohmmeter at the rear of the BIP, indicate the match up of the
battery lead with its return by placing the positive lead of the meter on the
A1+ stud and the negative lead of the meter on the A1- stud. A normal
reading is approximately 6.5 K ohms because of the capacitors inside the
BIP. Repeat this step for the A2, B1, and B2 feeds.
If the ohmmeter points to the infinity symbol (open circuit) or displays “0.L”
(overload) for a pair, a discontinuity exists in that pair. To perform power
reversal checks, place a short circuit between the A1+ and A1- studs.
Measure the resistance across the B1+ and B1- studs. A reading of 0
(zero) ohms indicates the battery leads are reversed. Remove the short
circuit from the A1+ and A1- studs, and measure the resistance between