Secutron MR-2100

MR-2100/MR-2200 Installation Manual
24
5.2 Battery Selection Calculations
1. From previous calculations, locate total Standby Current (A) and convert to amperes. A =
________
(Note: amperes = mA ÷ 1000; µA ÷ 1,000,000; examples: 250 mA = 0.25 A; 1500 µA =
0.0015 A)
2. Identify Standby Time (C), in hours. C = ______ (typically 4, 24, 48, or 60 hr)
3. From previous calculations, locate total Alarm Current (B) in amperes. B = ______
4. Identify Alarm Time (D) in minutes. D = ______ (typically 5, 10, or 15 min)
5. Using the values in Steps 1-4, perform an Initial Battery Calculation per the following:
(A x C) + (0.0167 x B x D) = _______ Ah (Ah = ampere hours)
6. Select a battery size LARGER than the number from the Initial Battery Calculation from
the following list of SOTA batteries using the 20 Hour Rating value:
If either the Standby Current or the Alarm Current is greater than the C/20 current for the initial
battery size selected, a discharge factor must be applied per the following table (use the 20 hr
value for 24 hr standby):
Standby Discharge Factor (SDF) = _________ Alarm Discharge Factor (ADF) = _________
7. Minimum Required Battery Capacity Calculation. (to account for battery aging, a 1.17
multiplier is included)
Minimum battery capacity in Ah =
1.17 x [(A x C x SDF) + (0.0167 x B x D x ADF)] = _______
8. If the battery size initially selected is smaller than the result of step 9 above, repeat the
calculations using a larger battery size.
Part Number
20
Hour
Rating
C/20
(Amps)
Part Number
20
Hour
Rating
C/20
(Amps)
MR-12V4.5AH 4.5 Ah 0.225 MR-12V18AH 18 Ah 0.9
MR-12V7.2AH 7.2 Ah 0.36 MR-12V26AH 26 Ah 1.3
MR-12V12AH 12 Ah 0. 6 MR-12V35AH 35 Ah 1.75
Discharge Time
Discharge
Factor
Discharge
Time
Discharge
Factor
Discharge
Time
Discharge
Factor
Discharge
Time
Discharge
Factor
0.083 hr 5 min 3.85 2 hr 1.43 8 hr 1.10 14 hr 1.03
0.166 hr 10 min 2.78 3 hr 1.30 9 hr 1.09 16 hr 1.02
0.249 hr 15 min 2.27 4 hr 1.22 10 hr 1.08 18 hr 1.01
0.332 hr 20 min 2.08 5 hr 1.18 11 hr 1.06 20 hr 1.00
0.5 hr 30 min 1.96 6 hr 1.14 12 hr 1.05 48 hr 1.00
1 hr 60 min 1.67 7 hr 1.11 13 hr 1.04 60 hr 1.00