Engineering guide
Eaton 93PM alarm indicators and system events
On an Eaton 93PM, a red indicator means an active alarm that needs immediate attention, and a flashing red indicator means a new alarm not yet acknowledged. Touch any control panel button to silence the horn, open LOGS to read the active alarms and notices, record them, and call a technician whenever the normal indicator is off or an alarm lamp stays lit.
Key facts
- Red indicator on: Active alarm, immediate attention
- Red indicator flashing: New alarm, not yet acknowledged
- Yellow bypass indicator: Load on bypass source; normal indicator off
- Event log: LOGS tab: active alarms, notices, commands
- Horn rate: Cycles at a half-second rate
The four status indicators
- Green on: double conversion mode, the power module is supplying the critical load.
- Yellow (battery) on: the UPS is in battery mode; the normal indicator stays lit because battery mode is a normal condition.
- Yellow (bypass) on: the load is on the bypass source, and the normal indicator goes out.
- Red on: an active alarm that requires immediate attention; the screen shows the highest priority alarms.
- Red flashing: a new alarm condition, flashing until acknowledged.
On a 93PM, the combination matters: yellow battery with green still on during an outage is the UPS doing its job; yellow bypass with green off means the load has lost conditioning.
The horn and the event log
Every alarm sounds the horn, which cycles at a half-second rate; touching any control panel button silences it. Silencing does not clear the cause. The LOGS tab opens the active events screen, which lists current alarms, notices and commands, and the log keeps the history a technician needs to see the order of events.
What the operator is expected to check
Eaton's daily routine for the operator is short: keep the area around the UPS uncluttered, make sure the front air intakes and rear exhaust are not blocked, keep the room within the specified environment, and confirm the normal indicator is lit. If an alarm lamp is lit or the normal indicator is out, the manual's instruction is to contact a service representative.
The monthly routine adds reviewing system parameters on the control panel and checking the air filter behind the front door. Everything inside the cabinet, including the battery string, belongs to trained service staff.
Battery-related events
Battery mode during an outage is normal. What is not normal is a short runtime, frequent transfers to battery, or alarms after a battery test. Those point to the string, and on a 93PM the string is often the oldest part of the system. Replacement battery strings for Eaton UPS should match the original block count and type, which is also what the manual requires for replacements.
When to call for service
- Red indicator lit, or flashing again after acknowledgement.
- Normal indicator off with utility present.
- Load on bypass that nobody requested.
- Any alarm that returns after it clears.
A scheduled visit catches fans, capacitors and battery wear before they become alarms; preventive service on Eaton and Powerware systems can be planned around your maintenance windows, and three-phase preventive maintenance lists what is checked.
Related pages
Common questions
How do I silence the alarm horn on an Eaton 93PM?
Touch any control panel button once. This silences the horn but does not clear the alarm or its cause.
What does a flashing red indicator mean?
A new alarm condition. It flashes until you acknowledge it by touching any control panel button.
Is the 93PM on battery a problem?
Battery mode is a normal condition during an input problem, and the green indicator stays lit. Repeated or unexplained battery operation should be investigated.
Where do I see the actual alarm message?
Select the LOGS tab on the main menu to open the active events screen with current alarms, notices and commands.
What can I check myself?
Clear access, unblocked intakes and exhaust, room conditions, and whether the normal indicator is lit. Anything else is for service staff.
Sources, checked October 4, 2026:
- Eaton 93PM-L 20-60 kW (208V) UPS Installation and Operation Manual, P-164000711 Rev 12, pp. 118 (PDF 130), 12 (PDF 24), 156 (PDF 168)
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