Federal Signal Corporation PS600 SelecTone, Инструкция по установке и обслуживанию

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12
Installation and Maintenance Instructions
Selectone Model PS600
The power supply must have enough capacity to properly operate
the external equipment. Calculate the standby current and the
twenty-four discharge rate on standby or the standby current and the
sixty hour discharge rate on standby. Determine the total ampere-
hour capacity necessary as described in the following example:
Discharge Rate: 24 hours
Standby current: 0.200 A, 24 Vdc
Five minutes Alarm Current: 6 A, 24 Vdc
Useful Battery Capacity: 85 percent
Capacity needed = (discharge rate [hours] x standby current
[amps]) + (alarm hours [hours] x alarm current [amperage])/useful
battery capacity
Capacity Required: ([24 x 0.200] + [5/60 x 6])/0.85
= ( 4.80 + 0.5)/0.85
= 5.30/0.85
= 6.23 Ah
In this example, a 24 Vdc, 6 A power supply with 24 V, 12 Ah
battery can operate the signaling device.
Determining the Maximum Load Discharge
Determining the maximum load discharge current from a specific
battery size over a specific amount of time can be tricky. Batteries
are rated at maximum efficiency over a 20 hour discharge period.
Therefore, a 20 Ah battery will provide 1 A over a 20 hour period.
However, calculating discharge time for other discharge currents
is not as easy as division or multiplication. A 20 Ah battery will
supply 1 A for 20 hours. However, it will not provide 2 A for 10
hours, but rather 1.8 A for 10 hours, which is equivalent to 18 Ah.