

What causes Optune alarms to go off?
Optune is designed to alert you if treatment is not being delivered. Find out what can cause your device’s alarm to go off and how to manage it.
Gill, an Optune® user and Patient Ambassador
If you hear an alarm, an issue may be occurring. Explore the possibilities below:
Are the arrays in good contact with your skin?
If not, using tape or Surgilast® can ensure good contact with the scalp.
When was the last time you changed your arrays?
Arrays should be changed at least 2 times per week (every 4 days at most).
Is there hair stubble beginning to grow?
Even if there is a small amount of hair growth, a new set of arrays should be applied after shaving. See Scalp Care Guide for more tips.
Are the arrays too warm?
Direct sunlight should be avoided. A breathable head covering could be helpful, as well as a fan. If sweat causes arrays to shift, they should be changed.

Is the yellow battery light on?
This is a great time to swap batteries for a full charge. When the battery is low, you will hear an alarm.
Have you checked the battery gauge?
If the gauge shows only 1 dot, the battery should be changed.

Are any transducer array connectors loose?
All array cables need to be fully inserted into the connection box.
Is the connection cable plugged into the device?
The gray connection cable should be gently inserted into the device with the arrows lined up. You should hear a click.

Are you hearing an alarm right after turning Optune on but BEFORE pressing the TTFields button?
Device should be turned off, and the battery changed. Then the device can be turned on.
Do you hear a rattling noise coming from the device, or has it been damaged?
You can call nCompass® support for troubleshooting assistance.

Need help troubleshooting Optune? nCompass® offers 24/7 technical support. Call 1-855-281-9301 any time of day, or email support@novocure.com.
nCompass cannot provide you with medical advice. Consult with your doctor for any medical questions.
If you turn Optune on without pressing the TTFields button, an alarm will sound after 10 minutes.
Press the TTFields button once to silence the alarm and twice to start therapy.
Osmond, an Optune® user and Patient Ambassador

What to do if your Optune device’s alarm goes off
Answer the following questions to help you identify the alarm that’s going off and what it means.

What does the alarm sound like?
When does the alarm occur?
When does the alarm occur or what lights did you see on the device?
Check both of the following:
Array Contact
Ensure good contact by pressing discs gently to scalp or use tape to secure the edges.
Sweat, moisture, or hair growth may cause arrays to lift. Shave head and change arrays as needed.
Array Temperature Too Warm
If outside, avoid direct sunlight. Wear a breathable head covering and/or use an umbrella to shade the array.
If sleeping or napping, roll onto a different side to release trapped warmth. A fan or cooling pillow may help.
Contact nCompass if the issue doesn't resolve.
Connections
Ensure connection cable is properly connected to the device with arrows aligned. The connector will click when fully connected.
Contact nCompass if the issue doesn't resolve.
Connections
Ensure transducer array connectors are fully inserted into the connection box.
Contact nCompass if the issue doesn't resolve.
Battery
Change the battery and power on the device again.
If alarm persists, call nCompass for troubleshooting assistance.
Contact nCompass if the issue doesn't resolve.
Therapy Timer
Press TTFields button once to silence alarm. Press TTFields button a second time to restart treatment.
Contact nCompass if the issue doesn't resolve.
Battery
If there are 1-2 lights on the battery gauge, change to a fully charged battery.
If there are 3-4 lights on the battery gauge, call nCompass for troubleshooting assistance.
Contact nCompass if the issue doesn't resolve.
Connection
Ensure array cables are properly connected to the connection cable.
Contact nCompass if the issue doesn't resolve.
Take the Optune Troubleshooting Tips brochure with you on the go.

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