TECOM TS1067E - Appendix B: Output Fusing and User Current Limits

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Appendix B: Output fusing and user current
limits
The current draw on the Network Access Controller for all user devices must not
exceed 3.5 A. This value excludes the standalone board current.
The Network Access Controller will shut down if this is exceeded.
e.g.: Battery chargers set to 550 mA, two batteries connected:
3.5 – 0.55 – 0.55 = 2.4 A max user load
e.g.: Battery chargers set to 1.2 A, one battery connected:
3.5 – 1.2 = 2.3 A max user load
In some environments, further restrictions on user current apply as detailed in
Appendix C.
On-board fuses provide over-current protection for devices as described in
Table 4 below. The numbers in the Item number column refer to items in Figure 2
on page 12.
Table 4: Maximum current draw per output
Device
Item number
Maximum current draw
Auxiliary power
7
1 A
Switched Auxiliary power
7
1 A
Siren output
8
2 A
Four onboard relays
11
2 A each (when using lock
power 12v and 0v)
Active relay coil
11
55 mA
Input expander
33
0.3 A
Relay expander
34
1 A
BUS 1
14, 15
1.0 A total
BUS 2
18
1 A
Wiegand
16
1 A
Consider the maximum current draw from the devices above when calculating
the total user current draw.