Posted on by

ISM, ISMe, and QSM11 – 018-021   Electrical System

Specifications

 TOC

Marine Applications

Starting Motor Circuit:

Maximum resistance:

12-VDC 0.00075 ohm
24-VDC 0.002 ohm

Starting Motor Circuit:

Maximum Voltage Drop:

12-VDC 1.95-VDC
24-VDC 1.7-VDC

Marine Applications

Unaided Cold Start:

Maximum Ambient Temperature -7°C [19°F]
Minimum Cranking Speed Required 120 rpm

Industrial Applications

Starting Motor Circuit:

Maximum resistance:

12-VDC 0.00075 ohm
24-VDC 0.002 ohm

Starting Motor Circuit:

Maximum Voltage Drop:

12-VDC 1.95-VDC
24-VDC 1.7-VDC

Industrial Applications

Unaided Cold Start:

Maximum Ambient Temperature -12°C [10°F]
Minimum Cranking Speed Required 120 rpm

Generator Drive Applications

Minimum Ambient Temperature for Cold Start With Coolant Heated to Rated Speed -14°C [7°F]
Minimum Ambient Temperature for Unaided Cold Start to Low Idle Speed -4°C [25°F]
Minimum Ambient Temperature for NFPA 110 Cold Start (90°F minimum coolant temperature) 0°C [32°F]

Minimum recommended battery capacity:

System Voltage
Ambient Temperature
-18°C [0°F]
0°C [32°F]
Cold Cranking Amperes
ReserveCapacity1Minutes
Cold Cranking Amperes
ReserveCapacity1Minutes
12-VDC
1800
640
1280
480
24-VDC2
900
320
640
240
  1. The number of plates within a given battery size determines reserve capacity. Reserve capacity determines the length of time that sustained cranking can occur.
  2. Cold Cranking Amperes rating are based on two 12-VDC batteries in series.

For automotive applications a minimum of 9-VDC at the power connector is required to power up to the ECM. For Industrial, Power Generation, and Marine Applications a minimum of 6.5-VDC at the power connector is required to power up the ECM.

Batteries (Specific Gravity)

 TOC

Specific Gravity at 27°C [81°F]
State of Charge
1.260 to 1.280
100%
1.230 to 1.250
75%
1.200 to 1.220
50%
1.170 to 1.190
25%
1.110 to 1.130
Discharged


Maximum Resistance of Starting Motor Circuit

12-VDC Starting Motor (Ohm) 0.00001

24-VDC Starting Motor (Ohm) 0.00020

Cable resistances can be obtained in the accompanying Battery Cable Resistance Chart. If the frame is in ground circit the frame length must be considered cable of the same size as that used in the balance of the system.

Item
Resistance Ohms
Connection
0.00001
Additional Contacter (Series-Parellel Switch, Relays, etd.)
0.00020
 
SMALL | MEDIUM | LARGE
Last Modified:  06-Feb-2009
Avatar photo

Published by Jack

Hello, I'm Jack, a diesel engine fan and a blogger. I write about how to fix and improve diesel engines, from cars to trucks to generators. I also review the newest models and innovations in the diesel market. If you are interested in learning more about diesel engines, check out my blog and leave your feedback.