Allen-Bradley 825-P, User Manual

Page: 159 / 266

Rockwell Automation Publication 825-UM004D-EN-P - November 2012 159
Testing & Troubleshooting Chapter 11
5.
Replace the fuse with a BUSS 2A/250V ABC (ceramic) or equivalent.
6. Insert the printed circuit board into Slot A.
7.
Reinstall the relay rear panel, ground screw, and eight rear panel screws.
8. Energize the relay.
Real-Time Clock (RTC) Battery Replacement
The RTC battery, which is a 3V lithium coin cell battery (Rayovac BR2335 or
equivalent), performs the following functions:
• Powers the clock (date and time) if the external power source is lost or
removed.
•
Retains the thermal memory for the thermal overload function when the
power source is lost or removed.
• Operates nominally at room temperature (25°C) for ten years at rated
load.
•
Experiences a low self-discharge rate when the relay is powered from an
external source. Thus, battery life can extend well beyond ten years. The
battery cannot be recharged.
To replace the real-time clock battery, perform the following steps:
1.
De-energize the relay.
2. Remove the eight rear panel screws, ground screw, and relay rear panel.
3.
Remove the Slot B printed circuit board.
4. Locate the battery clip (holder) on the circuit board.
5.
Remove the existing battery from beneath the battery clip.
6. Properly dispose of the battery.
7.
Install the new battery, 3V lithium coin cell battery (Rayovac BR2335 or
equivalent), with the positive (+) side facing up.
8.
Insert the printed circuit board into Slot B.
9. Reinstall the relay rear panel, ground screw, and eight rear panel screws.
10.
Energize the relay.
11. Set the relay date and time.