PowerCAD for Windows - User Guide
Ohm's Law Calculation:
Ohm's Law Calculation determines voltage, current, resistance and power when
any two parameters of
four are given:
-
Example:
- Voltage = 12Vdc
- Current = 2 Amp
Enter the information into the Appropriate Windows and Select "Calculate". The Resistance (6 Ohms) and Power ( 24 Watts) will be calculated.
Wire Size Calculation:
Wire Size Calculation determines the proper wire sizing for the entered parameters
of voltage,
current, wire run distance,temperature and percent degradation. The distance
can be given in
English or Metric units by selecting "Edit / Settings". For
example, 12 V System is powering
an egress door, drawing 1A, 200 feet away and the voltage cannot drop below
10%:
-
Example:
- System Voltage = 12Vdc
- Current Draw = 1
Amp
- Distance = 200
feet
- Percentage Voltage = 10%
Enter the information into the Appropriate Windows and Select "Calculate". The Wire Size
(14 AWG) and the End of Line Voltage (10.968 Vdc) will be calculated.
Voltage Drop In Existing
Wire Run:
Voltage Drop determines the voltage drop across an existing wire and calculates
the voltage at
the end of the run. This calculation is based on a continuous run of wire and
the load at the end of
the run. If determining voltage drops in segments, as in a fire alarm notification
loop application:
-
Example:
- System Voltage = 12Vdc
- Length of wire = 200
feet
- Current Draw = 1
Amp
- Wire Size = 18
AWG
Enter the information into the Appropriate Windows and Select "Calculate". The Voltage Drop
across the Wire Run (2.604V), the Voltage at the end of the Run (9.396V) and the Percent
Degradation (21.7%) will be calculated.
Battery AmpHour (AH)
Calculation:
Battery AmpHour Calculation determines the minimum amphour capacity required
for a given
systems parameters. For example, system required 1.5 Amps for 12 hours
of Standby Power,
and 3 Amps of Alarm Current for 5 minutes when a Power Failure occurs:
-
Example:
- Standby Current = 1.5
Amps
- Standby Time = 12
Hours
- Alarm Current = 3
Amps
- Ring off Time = 5
Minutes
Enter the information into the Appropriate Windows and Select "Calculate". The minimum
Amphour capacity (20.04AH) will be calculated.
System Standby with
Existing Battery:
System Standby will determine how long a battery will provide power for given
systems
parameters. For example, The System requires 2.2 Amps of Standby Current
and 5 Amps of
Alarm Current for 10 minutes. The System has a 34 AmpHour Battery. How many
Hours of
Backup will this Battery provide?
-
Example:
- Existing Battery Size = 34
AmpHour
- Standby Current = 2.2
Amps
- Ring off Time = 10
Minutes
- Alarm Current = 5
Amps
Enter the information into the Appropriate Windows and Select "Calculate". The maximum
standby time (14.61 Hours) will be calculated.
Transformer Sizing:
Transformer Sizing determines what Size Transformer your system requires. Transformer
are
rated in VA (Volt/Amps). For example, The System requires 12 Volts AC,
2 Amps AC, what size
Transformer is required?
-
Example:
- 12 Volts AC
- Secondary Current = 2
Amps AC
Enter the information into the Appropriate Windows and Select "Calculate". The Transformer
Size (24 VA) will be calculated.
Pop-Up Windows Calculator:
The Standard Windows Calculators appears on-screen when "Calculator" is
selected.
IMPORTANT NOTICE: AlarmSaf PowerCAD is updated periodically, however, it may not be up-to-date with all regulatory changes in all jurisdictions. Compliance with regulations is the sole responsibility of the user.
