In Eaton’s 9PX, 9SX and 5PX G2 manuals, alarms are listed by name, such as “Battery low”, with an LED and a beep pattern. One beep every 10 seconds: on battery. Every 3 seconds: battery low or overtemperature. Continuous: no battery, a failed battery test (9PX, 5PX G2), or a fault. Press ESC to silence it.
Silencing does not clear the cause. If the alarm status changes, the UPS beeps again. The tables below give each message, what Eaton says it means and the first step Eaton’s manuals give, then when the job needs a technician.
How these Eaton units report a problem
Eaton’s 9PX and 5PX G2 manuals sort what the UPS reports into three levels:
- Events are silent status information recorded in the Event log, such as “AC freq in range”.
- Alarms are recorded in the Event log and shown on the LCD status screen with the logo blinking. Some are announced by a beep every 3 seconds, such as “Battery low”.
- Faults are announced by a continuous beep and the red LED, recorded in the Fault log and shown on the LCD in their own message box, such as an output short circuit.
The 8 and 11 kVA manual adds that the alarms on the control panel usually do not mean the output power is affected: they are preventive alarms meant to alert you.
| Indicator | What Eaton says it means |
|---|---|
| Green on | The UPS is operating normally, in Online or High Efficiency mode |
| Orange on | The UPS is on Battery mode or on Bypass mode (the manual lists an orange indicator for each) |
| Red on | The UPS has an active alarm or fault |
| Beep | Messages that use it (models) |
|---|---|
| 1 beep every 10 seconds | Battery mode, a utility failure (9PX, 9SX, 5PX, 5PX G2) |
| 1 beep every 3 seconds | Battery low (9PX, 9SX, 5PX, 5PX G2); UPS overtemperature (9PX, 9SX, 5PX G2) |
| 1 beep every second | Site Wiring Fault (9SX 700 to 3000 VA) |
| Continuous | No battery (9PX, 9SX, 5PX G2); Battery fault (9PX, 5PX G2); Power overload (9PX, 9SX); Input or Output bad wiring (8 and 11 kVA); faults (9PX, 9SX, 5PX G2) |
| No beep | AVR mode, utility voltage outside normal thresholds (5PX, 5PX G2; the 5PX manual adds that the equipment is still normally protected) |
Eaton 9PX and 9SX alarm table (700 to 3000 VA)
This table follows the manual for the 9PX 700 to 3000 VA. The 9SX manual lists Battery mode, Battery low, No battery, Battery fault, Power overload and UPS overtemperature, and adds the Site Wiring Fault.
| Message | What it means | First step in Eaton’s manual | Beep |
|---|---|---|---|
| Battery mode | A utility failure has occurred and the UPS is powering the equipment from the battery | Prepare your equipment for shutdown | 1 every 10 s |
| Battery low | The battery is running low. The warning is approximate; depending on load and the number of Extended Battery Modules (EBMs), it may come before the batteries reach 20% capacity | Shut down applications on the connected equipment: automatic UPS shutdown is imminent | 1 every 3 s |
| No battery | The batteries are disconnected | Verify that all batteries are properly connected; if it persists, call for service | Continuous |
| Battery fault | The battery test failed due to bad or disconnected batteries, or the battery minimum voltage was reached in ABM cycling mode | Verify the battery connections, then start a new battery test; if it persists, call for service | Continuous |
| Bypass mode | An overload, a fault or a command put the UPS in Bypass: equipment is powered but not protected | Look for an overtemperature, overload or UPS failure alarm | LED on |
| Power overload | The load is above 100% of the UPS rating | Remove some equipment. The UPS keeps running but may switch to Bypass or shut down if the load increases; the alarm resets when the condition clears | Continuous |
| UPS overtemperature | The internal temperature is too high or a fan has failed | If it persists, shut down the UPS, clear the vents, remove heat sources, let it cool, make sure air can flow, then restart. If it still persists, call for service | 1 every 3 s |
| Site Wiring Fault (9SX) | The ground connection is missing, or line and neutral are reversed at the wall outlet | Have a qualified electrician correct the wiring. On the 9SX1000G, 9SX1500G, 9SX2000G, 9SX3000G and 9SX3000GL, which have no neutral, Eaton says to disable the Site Wiring Fault Alarm setting | 1 every second |
| UPS does not start | The input is not connected correctly, or the Remote Power Off (RPO) input is active | Check the input connections; if the status menu shows “Remote Power Off”, deactivate the RPO input |
A short backup time has its own line in the same table: the batteries need charging or service. Eaton’s step is to apply utility power for 48 hours, then call for service if it persists.
The 8 and 11 kVA manual (European edition) adds three messages. Input bad wiring or Output bad wiring (continuous beep) means the cables are not on the correct terminal blocks. MBP disconnected means the HotSwap MBP is no longer connected to the UPS; if it is in place, check that its detection connector is plugged in.
Eaton 5PX: first generation and G2
The 5PX has two manuals. G2 part numbers end in G2, for example 5PX1500RTG2. The first-generation manual lists fewer messages and gives beep patterns only for battery operation and AVR mode.
| Condition | 5PX (first generation) | 5PX G2 |
|---|---|---|
| On battery | Battery LED on, 1 beep every 10 seconds | 1 beep every 10 seconds |
| Low battery | 1 beep every 3 seconds (indicator solid; it blinks at end of backup time); may come before the battery reaches 25% capacity | 1 beep every 3 seconds; may come before 20% capacity remains |
| Batteries missing | “Batteries disconnected”: verify that all batteries are properly connected | “No battery”, continuous beep: verify the battery connections |
| Overload | Above 105% of nominal: remove some equipment | Above 100% of nominal: remove some equipment |
| Overtemperature | Not in the troubleshooting table | 1 beep every 3 seconds; 10°C above the warning level the UPS shuts down |
| Battery life | “End of battery life”: contact your service representative for replacement | Battery Age warning, default 48 months, adjustable |
| Internal failure | “UPS fault”: the UPS does not protect the equipment anymore | Fault in the Fault log |
On the first-generation 5PX, “Reset fault state” clears an active fault, and the UPS must then be restarted.
Overtemperature and overload: what the UPS does next
At the overtemperature warning level, the 9PX keeps running in its current mode. If the temperature rises another 10°C, it transfers to Bypass, or shuts down if Bypass is unusable, and returns to normal operation when the temperature drops 5°C below the warning level. The 5PX G2 has no such step: 10°C above the warning, it shuts down.
In Bypass the 9PX passes utility power through, passively filtered. Battery mode is not available and the equipment is not protected. After an overload it stays in Bypass for at least 5 seconds, and it stays there if three transfers to Bypass occur within 20 minutes.
For why a UPS goes to bypass and what to check before returning it to normal mode, see Eaton UPS on bypass: what it means and what to check.
| Load (percent of rating) | Online mode | Battery mode | Bypass mode |
|---|---|---|---|
| 102 to 110% | 12 s (transfer depends on the Output mode setting) | 12 s, then the output stops | Overload warning |
| 110 to 130% | 12 s (transfer depends on the Output mode setting) | 12 s, then the output stops | Shutdown after 5 minutes |
| 130 to 150% | 2 s | 2 s | Shutdown after 15 s |
| Above 150% | Shutdown after 300 ms | 2 s | Shutdown after 300 ms |
The overload pre-alarm is set by load percentage: default 102% on the 9PX, 105% on the 5PX G2.
Battery alarms, the 4-year notice and new batteries
The 9PX manual gives an expected battery life of 3 to 5 years and states that it halves for each 10°C above 25°C; it asks for a 25°C room for full battery life. After 4 years of operation the 9PX and 9SX display a battery replacement notice; on the 9PX the recommended replacement date is under Measurements, then Battery. On the 5PX G2 the Battery Age warning defaults to 48 months and can be set from 6 to 120. The 9PX maintenance section says batteries used beyond their service life often have severely reduced runtimes, and to replace batteries at least every 4 years.
On a 9PX the batteries can be replaced without turning off the UPS or disconnecting the load, but never while it is in Battery mode. The manual asks for qualified service personnel and the same type and number of batteries, and lists these precautions:
- Remove watches, rings and other metal objects.
- Use tools with insulated handles.
- Do not lay tools or metal parts on top of the batteries.
- Wear rubber gloves and boots.
The first-generation 5PX manual warns that the battery can cause electrocution and high short-circuit currents, and says to disconnect a battery module by separating its connectors, never by pulling on the wires. Up to four EBMs can be connected to a 9PX; an EBM is heavy, and lifting one into a rack takes at least two people.
To test new batteries, Eaton’s sequence is:
- Charge the batteries for 48 hours.
- Press any button, then select Control, then Start battery test.
- The test starts only if the batteries are fully charged, the UPS is in Normal mode with no active alarm, and the bypass voltage is acceptable. The UPS then runs on battery for 25 seconds.
The automatic test runs weekly in constant charge mode, or at each cycle in ABM mode, and discharges the batteries for 10 seconds. The low battery alarm does not activate during a test, and a test can be postponed by bad conditions. Leave deep discharge protection on: Eaton states the warranty is void if it is disabled. In storage, recharge every 6 months.
Reading the Event log and Fault log
Both logs are on the front panel. Press any button to open the menu, select Event log or Fault log, and scroll through the entries. Alarms are in the Event log; faults are in the Fault log. Before calling for service, Eaton lists what to have ready:
- Model number and serial number
- Firmware version number
- Date of the failure or problem
- The symptoms of the failure or problem
Silencing the beeper
Press ESC on the front panel. The beeper sounds again if the alarm status changes. On the 9PX, the Audible alarm setting offers Enabled (the default), Disabled on battery and Always disabled. The first-generation 5PX setting is Yes or No.
When to call a technician
- A continuous beep that returns after you have checked the battery connections and run a new battery test.
- Battery fault or a short backup time after 48 hours on utility power.
- The UPS keeps going to Bypass: three transfers within 20 minutes hold it there, and the load is unprotected.
- Overtemperature that comes back after the vents are clear and the room is cool.
- UPS fault on a first-generation 5PX: Eaton states the UPS no longer protects the equipment.
- The 4-year battery notice, or EBM replacement: Eaton says lifting an EBM into a rack takes at least two people.
We service Eaton 9PX, 9SX and 5PX units across Canada: see battery replacement, emergency repairs, UPS maintenance or contact us at 438-800-0382.
Frequently asked questions
What do the beeps on an Eaton UPS mean?
On the 9PX and 9SX: one beep every 10 seconds, on battery; one every 3 seconds, battery low or overtemperature; one every second (9SX), Site Wiring Fault; continuous, no battery, a failed battery test (9PX), a power overload or a fault. The 5PX G2 uses the same 10 and 3 second patterns.
How do I stop my Eaton UPS from beeping?
Press ESC on the front panel. It beeps again if the alarm status changes. On the 9PX, the Audible alarm setting can also be set to Disabled on battery or Always disabled.
Why does my Eaton UPS show Battery fault after a battery replacement?
Battery fault means the battery test failed on bad or disconnected batteries. Check every connection, charge 48 hours, then start a new test: it runs only with full batteries, Normal mode, no active alarm and acceptable bypass voltage.
What does Bypass mode mean on an Eaton 9PX?
The UPS passes utility power to the equipment after an overload, a fault or a command. The equipment is powered but not protected. Look for an overtemperature, overload or UPS failure alarm.
Why is my Eaton UPS asking for a battery replacement?
The 9PX and 9SX display a replacement notice after 4 years of operation. On the 5PX G2 the Battery Age warning defaults to 48 months and can be changed.
What is Site Wiring Fault on an Eaton 9SX?
The ground connection is missing, or line and neutral are reversed at the outlet. Eaton says to have a qualified electrician correct the wiring. On the 9SX1000G, 9SX1500G, 9SX2000G, 9SX3000G and 9SX3000GL, which have no neutral, Eaton says to disable the Site Wiring Fault Alarm setting.
Sources
- Eaton, 9PX 700 to 3000 VA Installation and user manual. Indicators, status table, overload table, battery maintenance, troubleshooting.
- Eaton, 9SX 700 to 3000 VA Installation and user manual. Troubleshooting, Site Wiring Fault.
- Eaton, 9SX/9PX 8000 and 11000 Installation and user manual (European edition). Wiring and MBP messages.
- Eaton, 5PX 1000 to 3000 Installation and user manual (614-03797-00). First-generation messages, battery safety.
- Eaton, 5PX G2 Advanced User Guide (614-40095-00). G2 alarms, settings, silencing.