Tyco F3200 - Manual (Page 58)

F3200 Installation & Programming Manual Document No: LT0122
Configuring a FIP
Page 5-4 5 July 2001 Issue 2.7
GENERAL (CONTINUED)
4. The approvals laboratory recommends using 90% derating of batteries used on
F3200 because the battery fail voltage (Standby) is 22V instead of 21V (as used on
some other FIPs). The local approval body may not require this, however, because
although the F3200 will not generate new alarms below the "battery fail voltage", it
will maintain any alarms and outputs that occurred when the voltage was higher than
the battery fail voltage. AS1670.1 1995 does, however, recommend 80% derating of
batteries for the effect of ageing, ie. multiply the required battery capacity (at end of
life) by 1.25 when calculating the required capacity for a new battery.
5. For maximum physical battery sizes refer to "Battery Size". (Refer to Section 5.3.4).
5.3.2 BATTERY/CHARGER CALCULATIONS
The recommended order of calculations is as follows:
1. Calculate the FIP quiescent load (Iq) from the figures given in Section 3.3.5. Note
that the detector load for each AZC has to be added to the quiescent current per
AZC. Calculate In separately, where In is the external non-alarm, non-battery
backed load on the FIP PSU (e.g. door holders).
2. Calculate the FIP alarm load (Ia) for 2 zones in alarm from Section 3.3.5. (Include all
external loads e.g. bells, relays).
3. Calculate the 5 hour/0.5 hour battery capacity for the charger requirement as follows:
Cap (5 hr) = (5 x Iq) + (0.5 Ia x 1.33) Ahr
= 5Iq + 0.66Ia where
Iq = quiescent current
Ia = alarm current
Note that the 1.33 multiplier increases the required capacity to allow for an alarm
load of up to 10 times the quiescent load (i.e. 75% derating of capacity).
4. Find the greater of Iq + In, or Ia. Calculate the power supply/charger requirement (Ic)
as follows and check that it is less than 3A. (If greater a 6A charger is required).
Ic = I + Cap (5 hr) ÷ 24e where I is the greater of Iq + In, or Ia, and e is the changing
efficiency of the particular battery being used, at the current being used (typically
80%, ie. (cap/24) x 1.25).
5. Calculate the battery capacity as follows:
Cap (24 hr) = (24 x Iq + 0.66 Ia) x 1.25
(See note 4 of Section 5.3.1 regarding the x 1.25 multiplier).
Select a battery which has a rated capacity (i.e. 20 hr rating) equal to or above that
just calculated. (Refer to Sections 3.3.3 and 5.3.4 for approved types).