GE PLC Battery and Capacitor Capacity

We came across this document today that we thought might be helpful in understanding the capacity of Battery back-up and Capacitor back-up of programs in GE Versamax PLCs,  GE 90-30 PLCs, GE 90-70 PLCs, and PAC systems:

GE PLC Battery and Capacitor capacity

For VersaMax CPUs

Refer to IPI of VersaMax CPU modules:

• Battery backup for program, data, and time of day clock
• Super capacitor provides power to memory for 1 hour
• Over 1 hour, backup battery protects memory contents up to 6 months.
• Backup battery has shelf life of 5 years when not in use.

The part number is IC200ACC001.

For VersaMax Micro 23/28 point PLC

Capacitor backs up RAM and the Time-of-Day clock for at least 30 minutes.

Lithium battery (IC200ACC403, optional battery):

Shelf Life: Up to 5 years typical at 30 °C, Up to 3 years typical at 55 °C

Installed: 4 months battery backup time (powered down) minimum at 55 °C

For VersaMax Micro 14 point PLC and Nano PLC

Capacitor backs up RAM for at least 3 days.

There is no optional battery for 14 point Micro and Nano PLC.

For Series 9030 PLC

Super Capacitor:

The PLC power supply supplies 5 VDC to the memory circuits, including the super capacitor. Therefore, when PLC power is turned off, the super capacitor has an initial 5 VDC charge. If the battery is also disconnected shortly after PLC power is turned off, the super capacitor will begin discharging from the 5 VDC level until its charge reaches 2 VDC, at which time memory contents will be lost. When used this way, the super capacitor can maintain memory contents for a minimum of 1 hour.

The memory backup battery supplies 3 VDC to the memory circuits, including the super capacitor. Therefore, if PLC power has been turned off for an hour or more and only the battery is powering the memory circuits, the super capacitor has a 3 VDC charge. Then, if the battery is disconnected, the super capacitor will begin discharging from the 3VDC level until its charge reaches 2 VDC, at which time memory contents will be lost. When used this way, the super capacitor can maintain memory contents for a minimum of 20 minutes.

Battery: IC693ACC301 battery lit for 9030 CPU and PCM (qty 2)

A battery that is used continuously (supplying current to memory circuits with PLC power off), if used at room temperature, has an estimated average life as follows:

Model	Estimated Average Life with internal battery (Installed in Power Supply)	Estimated Average Life with external battery (IC693ACC302)
CPU Models 311, 313 and 323	2 years	NA
CPU Models 331 - 364	1 year	75 months
CPU Modules 374	1.2 months	15 months
S9030 ENIU – IC693NIU004	1.2 months	15 months

The voltage threshold for the BATT LED to come on in a 90-30 powers supply is 2.5V DC +/- 5%

External Battery Module (IC693ACC302)

This module provides long-term battery backup for all modular Series 90-30 CPUs. Its two-foot cable plugs into the power supply battery connector. The External Battery Module maintains RAM contents on a CPU374 and NIU004 for 15 months. CPU models 331—364 maintain RAM contents for approximately 75 months.

For Series 9070 PLC

IC697ACC701 battery lit for 9070 CPU and PCM (qty 2)

A battery that is used continuously (supplying current to memory circuits with PLC power off) has an average estimated life of 6 months, if used at room temerature.

The voltage threshold for the BATT LED to come on in a 90-30 powers supply is 2.5V DC +/- 5%

For PACSystem RX7i PLC

IC698ACC701 --- A battery that is used continuously (supplying current to memory circuits/calendar with system power off) has a minimum estimated life of 40 days.

If want to keep program forever, write HWC and Logic into Flash memory.