May 2022
EXTENDED RUNTIMES FOR INVERTERS
TOPIC
Background
Product Specifications
- NFPA 101 Minimum Requirements
Wrapping Up
- Extended Run Time Options
- More Information About Batteries Than You Care About...
- How To Get More Information
- Why Might You Need More?
- Product Derating
- Motor Load Calculations
Chalk Talk
Overview
Minimum Requirements
- Lights must be on at emergency levels within 10 seconds of an emergency
NFPA101, Per Usual
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
I. BACKGROUND
- Lights must remain above 60% of initial illumination levels for at least 90 minutes.
- Generally, all emergency fixtures are overprovisioned a fair amount to make sure that they last for a long time in the field
- A new-in-box emergency light might run for 150 minutes or more
Why Might You Need More?
- Some facility types are mandated by local code to have longer run times (2 hours is common).
Local/Regional Codes
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
I. BACKGROUND
- Non-Life Safety Shelter In Place Areas (Common Spaces)
- Residential/Mixed Use Applications
- Outdoor Lights
Performance and Preference Reasons
- Areas designated for sheltering in place often require run times of 4 hours.
Extended Run Time Options
- We use EB to designate "extended battery" and extended run times
Specific Options to Modify Capacity or Ratings
II. PRODUCT SPECIFICATIONS
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
- On E3MINI selecting EB increases run time to 2 hours at the expense of maximum capacity (100VA & 200VA)
- On E3 selecting EB increases the run time to 2 hours at with no maximum load reduction
- We use higher capacity batteries for these applications
What if you need more than 2 hours?
Why doesn't the E3MAC have an EB option?
Product Derating
- Inverters are rated in W/VA but the important thing is Wh/VAh
- 1000W for 90 minutes = 1500 Wh
- This means that for a given wattage rating, we can work out run time
- For example, consider
The Linear Method
II. PRODUCT SPECIFICATIONS
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
500W of load on our 1500 Wh inverter
1500 Wh / 500 W = 3 hours = 180 minutes
250W of load on our 1500 Wh inverter
1500 Wh / 250 W = 6 hours = 360 minutes
-or-
Battery Master Class
- The slower you discharge a battery, the more effective capacity it has.
Battery Are Complicated (and Cool)
II. PRODUCT SPECIFICATIONS
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
- Amp-Hour ratings assume a discharge rate, 1C, discharging faster reduces capacity, discharging slower increases capacity.
Your Run Times Will Be Better than the Linear Analysis Would Suggest
Let Us Do This Calculation For You, Please
BATTERY DERATING CHART
Motor Loads on Inverters
- Things You Need to Know:
The Most Complicated Math Yet!
II. PRODUCT SPECIFICATIONS
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
1. Locked Rotor Current
2. Motor Efficiency
3. Horsepower/Wattage
4. FLA (Full Load Amperage)
Motor Loads on Inverters
What You Need To Know!
II. PRODUCT SPECIFICATIONS
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
- FLA * 6 < Inverter Amperage * Crest Factor
- Motor Horsepower * Pf * Efficiency < Rated Amperage
Locked Rotor Current
FLA
- Inverter Rated Amperage = Rated Wattage / Voltage
- Conversion: 1HP = 745.7 Watts
- Typical Motor Power Factor: 0.6 (or Read the Label)
- Typical Motor Efficiency: 0.8 (or Read the Label)
Short Form
- Use the simple linear formula for all cases to get a quick answer
- Call Isolite if you need to sharpen the pencil on run times
- Motor loads should always be reviewed by the engineer and probably with Isolite as well
Extending Run Times
III. WRAPPING UP
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
Environmental Considerations
- Batteries that are too hot or too cold have reduced capacity
- If you have very long run times, don't forget the HVAC will probably be off during an emergency
Sales Materials
- Training Video Link (Public - For Agent Only)
- Sales Presentation PDF (Public - For Agent Sales Presentations)
Available within Follow-up Sales Packet
III. WRAPPING UP
ISOLITE
EXTENDED RUNTIME FOR INVERTERS
Chalk Talk
Team of Experts
Schedule a Webinar for Advanced Sales & Engineering Training
THANK YOU