Contact Us
604.284.5171
Subscribe
Menu
  • Shop
    • Electrical Orientation
    • Electrical Audit

    Power

    • AC & DC Panel
    • Accessories
    • Alternator
    • Battery
    • Battery Combiner
    • Battery Isolator
    • Battery Monitor
    • Charger
    • DC to DC Converter
    • External Regulator
    • Galvanic Isolator
    • Inverter
    • Inverter/Charger
    • Isolation Transformer
    • Methanol Fuel Cell
    • Solar Controller
    • Solar Panel

    Navigation

    • Accessories
    • AIS
    • Autopilot
    • Chartplotter/MFD
    • Depth Transducer
    • Instrument Packs
    • Instrument Display
    • NMEA 2000
    • Radar
    • Sensors
    • VHF Radio
    • Video Camera

    Communications & Entertainment

    • Accessories
    • Cell Booster
    • Satellite Data & Voice
    • Satellite TV
    • Sound System
    • WiFi Booster

    Comfort

    • Accessories
    • Heater
    • Water Maker
  • Consultation & Design
  • Installation & Service
  • Resources
    • Videos
    • Boating Tech Talk
    • Diagrams
    • Articles
    • Tech Talk
    • Hotwire
  • About
    • About PYS
    • Case Studies
    • Testimonials
    • Events
    • Women's Day
    • Media
    • PYS Merchandise
    • PYS Donation
    • Careers
    • Contact
  • Home
  • Shop
  • Consultation & Design
  • Installation & Service
  • Resources
    • Videos
    • Boating Tech Talk
    • Diagrams
    • Articles
    • Tech Talk
    • Hotwire
  • About
    • About PYS
    • Case Studies
    • Testimonials
    • Events
    • Women's Day
    • Media
    • PYS Merchandise
    • PYS Donation
    • Careers
    • Contact
  • HOME
  • ResourcesVideosWhat Is the Depth of Discharge for My…
Power
  • AC & DC Panel
  • Accessories
  • Alternator
  • Battery
  • Battery Combiner
  • Battery Isolator
  • Battery Monitor
  • Charger
  • DC to DC Converter
  • External Regulator
  • Galvanic Isolator
  • Inverter
  • Inverter/Charger
  • Isolation Transformer
  • Methanol Fuel Cell
  • Solar Controller
  • Solar Panel
Navigation
  • Accessories
  • AIS
  • Autopilot
  • Chartplotter/MFD
  • Depth Transducer
  • Instrument Packs
  • Instrument Display
  • NMEA 2000
  • Radar
  • Sensors
  • VHF Radio
  • Video Camera
Communications
& Entertainment
  • Accessories
  • Cell Booster
  • Satellite Data & Voice
  • Satellite TV
  • Sound System
  • WiFi Booster
Comfort
  • Accessories
  • Heater
  • Water Maker

Actisense

Airmar

B&G

Balmar

Battle Born

Blue Sea Systems

EFOY

Emtrak

Espar

FCI

FLIR

Firefly

Furuno

Fusion

Garmin

Genasun

Gioco

HOLMES

ICOM

Intellian

KVH

Lowrance

Maddox

Navico

PYS

Promariner

Raymarine

SIMRAD

Seaview

Shakespeare

Sol-Go

Solara

Solbian

SunPower

Vesper

Victron

Wave WIFI

Xantrex

What Is the Depth of Discharge for My AGM Battery?

View Transcript
Hide Transcript

Transcript is auto-generated.

hi

everyone jeff cote here with

boatingtechtalk.com

all right so we've got a question from

a fellow motor stormer asks jeff

regarding the victron smart battery

protect what kind of voltage or battery

percentage do you usually set out

for the cutout at it's just a single

house battery at 120 amp hours

tough question good one but tough mmm

okay so we all know

that um generally for flooded lead acid

batteries

generally the floor is about 50

of dod depth of discharge so 100 full

battery

zero percent full battery 50 right in

the middle is sort of a

healthy sort of point where you're going

to have reasonable amount of cycles

and a reasonable amount of depth of

discharge naturally if you

discharge your battery only from 100 to

90 percent you'd have way more cycles

but you're constantly having to recharge

so it's all about finding that balance

between

you know just stopping discharging your

battery at 90 or stopping discharging

your battery at zero

and generally the compromise with

flooded lead acid batteries is about

50 now we also know that agm batteries

which are absorbed glass mat batteries

still let acid not flooded right so

in here with an agm battery the

electrolyte is in a glass mat

you can go deeper on the depth of

discharge some folks are going to bring

it down to 30 percent

and it's going to be for them a way to

compromise get more usable batter

battery out of the battery or capacity

and doing so knowing that they're going

to sacrifice

battery life because remember the deeper

you go on the discharge

the harder it is on the battery okay

fine

so where do we set ourselves for this

sort of

alarm or this set point i would say

that anywhere between 30

and 50 it really depends on how often do

you go to 50 and how often do you go to

30

if you never go to 50 and you always

stop discharging your battery around 60

some of the boaters that i know stopped

discharging even at 70 that's their

choice

well then maybe 50 is plenty right

because you don't want to have

something constantly alarming because

over time

uh you're gonna start disregarding that

information so you want this to be

exceptions

right like it never happens and when it

does you react to it

so maybe if you're discharging your

battery to 60 70 percent

and rarely to 50 then maybe put 50 as

the threshold

or you might be going to 50 40 35 all

the time

then set 30 percent of the threshold and

again

you always want to give yourself a

buffer right it's a little bit like a

gas tank

you know the gas tank might be rated at

70 liters let's say

but there might be your gauge is giving

you

says zero but there's still a little bit

more fuel in the tank

the lowest i would think is reasonable

for an agm battery

and this should never happen but when it

does it's serious and there's no turning

back meaning you've got to deal with it

right away

would be 20 so it cannot be lower than

20 but that's pretty damn low

so maybe bring it to 30 and if you don't

use your battery as deep then maybe stop

at 50.

so good question but there's no easy

answer there's no right

answer and a wrong answer it really

depends on how you use your battery bank

every day so great question stormer

thanks for asking

thank you for watching this pys video if

you've got further questions please ask

it below or contact

us on our contact form on our website

i'm happy to donate my time

to share information with you you can

support us in keeping our channel

ad free by purchasing some merch on our

store or making a donation through

paypal

and don't forget to subscribe thanks

again for watching

About PYS

PYS Electrical Design

2018 Boat Show Presentations

Boat Show 2018 - DIY Marine Electrical Connections

Boating Tech Talk

Can I Use a Battery Isolator With an Outboard Engine?

Boating Tech Talk

Can I Add New Batteries to an Older Existing Battery Bank?

Share This

Related Content

Our Marina Only Has 15A Shore Power but I Still Keep Tripping the Breaker?

Boating Tech Talk
Our Marina Only Has 15A Shore Power but I Still Keep Tripping the Breaker?

3 Bank Battery Charger for 2 Battery Banks?

Boating Tech Talk
3 Bank Battery Charger for 2 Battery Banks?

Can You Explain Battery Combiners, GFCI/ELCI vs. Galvanic Isolators?

Boating Tech Talk
Can You Explain Battery Combiners, GFCI/ELCI vs. Galvanic Isolators?

Adhesives for Flexible Solar Panels?

Boating Tech Talk
Adhesives for Flexible Solar Panels?

Explain Wire Size and Fusing?

Boating Tech Talk
Explain Wire Size and Fusing?

AIS Receiver vs. Radar Reflector?

Boating Tech Talk
AIS Receiver vs. Radar Reflector?

Advice on Selecting an Inverter/Charger?

Boating Tech Talk
Advice on Selecting an Inverter/Charger?

Common Reasons for Battery Damage?

Boating Tech Talk
Common Reasons for Battery Damage?

Advice on Marine Cameras?

Boating Tech Talk
Advice on Marine Cameras?

How are my Tach and Alternator Related?

Boating Tech Talk
How are my Tach and Alternator Related?

Experience with Thermal Cameras?

Boating Tech Talk
Experience with Thermal Cameras?

Automatic Combiner Relay or Voltage Sense Relay

Boating Tech Talk
Automatic Combiner Relay or Voltage Sense Relay

Can You Explain the Difference Between Poly and Mono Solar Panels?

Boating Tech Talk
Can You Explain the Difference Between Poly and Mono Solar Panels?

Two Batteries Are Hotter and Need More Refills Than the Other Batteries in the Bank - What Causes This?

Boating Tech Talk
Two Batteries Are Hotter and Need More Refills Than the Other Batteries in the Bank - What Causes This?

What Is The Charging Sweet Spot & Maximum Discharge For My Batteries?

Boating Tech Talk
What Is The Charging Sweet Spot & Maximum Discharge For My Batteries?

12V or 24V Thruster?

Boating Tech Talk
12V or 24V Thruster?

How Do I Prevent Galvanic Corrosion on My Boat From Boats Around Me?

Boating Tech Talk
How Do I Prevent Galvanic Corrosion on My Boat From Boats Around Me?

Gel Battery Rate of Charge?

Boating Tech Talk
Gel Battery Rate of Charge?

Advice on Improving Alternator Ouptut?

Boating Tech Talk
Advice on Improving Alternator Ouptut?

Help me Understand my Fuse Block?

Boating Tech Talk
Help me Understand my Fuse Block?


Pacific Yacht Systems

Copyright © 2023 Pacific Yacht Systems.

Contact Us
604.284.5171

We serve the Lower Mainland
and Southern Vancouver Island.

  • Subscribe

Subscribe

PYS Partners  |  Privacy Policy