System Power Factor Check Considerations - Toshiba Strara CTX Series Installation And Maintenance Manual

System Power Factor Check Considerations

The Strata CTX power supply was engineered for maximum cost efficiency to provide power for the
most configurations. Because of this design, there are some -24VDC power limitations for telephone
option hardware.
Each telephone/device and PCB has been assigned Power Factors (PFs) that reflect the amount of
power supply resources they consume. The Power Supply Unit has also been assigned Power Factors
that reflect how much power it can supply. To make sure the cabinet power supply is operating within
its limit, it is necessary to add up the PFs of each telephone/device and PCB installed in each cabinet to
verify that their total PFs do not exceed the Power Supply PF.
Use the tables provided on
Important!
Power Factor Considerations:
The individual PCB and telephone power factors can be found on
The sum of all PCB and telephones –24VDC PFs in a given cabinet cannot exceed:
85 for CTX670
45 for CTX100
The sum of all PCB +5VDC PFs in a given cabinet cannot exceed:
40 for CTX670
20 for CTX100
Telephones do not have +5VDC PFs.
If a cabinet PF is exceeded it is necessary to reconfigure the cabinet to meet PF limits.
If a cabinet's Power Factor is exceeded, cabinet or connected peripherals may malfunction during
ringing or voice paging, whereas normal operation will occur for idle telephones.
The Strata CTX100 and CTX670 power supplies provide a PF alarm LED and reset button. If this
LED is on, reset it with the reset button. Then recheck the cabinet PFs to make sure they are within
limits.
Notes
1. PCB Power Factor calculation examples are shown in
2. Please note some of the PCB's are only available in the US.
Table 1-16 Strata CTX Base Cabinet Example
PDKU
RBSU + RBSS
RCOU + RCOS
BBCU
BECU
Strata CTX I&M September 2002
pages 1-29 and 1-30
PCB Quantity
2
1
1
1
1
Total 6
to calculate that each cabinet PF is within limits.
Tables 1-16
+5VDC PF
1.6
3.1
3.6
4.5
4.5
17.3
Strata CTX Configuration
page 1-29.
and 1-17.
-24VDC PF
0.6
0.3
4.0
2.0
2.0
8.9
1-27