SUN SAFES MFG. CO. KOREA
SF680 Series
User Manual
Operating instructions for the KC-S electronic lock: opening, closing, changing your password and understanding the indicator lights.
Keep the door open after changing the password.
Test the new password before closing the safe. The green light confirms successful entry; a red light with beeps means the entry was not accepted.
1. Quick guide & first use
The KC-S lock uses * to begin password entry and # to confirm it. Include both keys in the opening sequence.
Open with your current password
* Current password #
Before storing valuables
- If the original password is still in use, follow the opening procedure with 123456.
- Set your personal password using the change switch in the lock case.
- Test the new password with the door open before closing the safe.
If the safe already has a personal password, use that current password. If it is unknown, contact the store where you purchased the safe.
Reference: PDF page 1, sections A, C–F.
2. Opening & closing
Open the electronic lock
- Press * first. A beep sounds and the red light turns on.
- Enter your current password. For a lock still using its initial setting, enter 123456. The manual describes a beep with the red light during entry.
- Press #. The lock operates and the green light turns on.
- Once the lock has released, open the door.
A red light during entry is part of the normal sequence. A flashing red light when you press * indicates low batteries. A red light with three beeps after an incorrect entry indicates rejection.
Close and lock
- Bring the door fully closed, keeping items clear of its path.
- Press #. The lock operates with the green light on.
- Check that the door is secured before leaving the safe.
If the door or locking mechanism cannot complete its movement, the manual describes three beeps at 10-second intervals. Check that the door can close correctly, avoid forcing the mechanism and contact the purchase store if the problem continues.
Reference: PDF page 1, sections A–B.
3. Changing the password
Open the door before beginning and locate the change switch in the lock case. Keep the door open throughout setup and testing.
- Press the change switch. A beep sounds and the green light turns on.
- While the green light is on, press *, enter your new password, then press #.
- Listen for three beeps, which the manual identifies as completion of the change procedure.
- Continue immediately to the open-door test below.
Change sequence
Change switch Green light * New password #
Reference: PDF page 1, section C.
4. Test the new password with the door open
Do not close the door until this test succeeds.
- Leave the door open.
- Press *, enter the new password, then press #.
- Check the light and sound using the guide below.
| Test result | Meaning and action |
|---|---|
| Green light on | The password was accepted. Once you have confirmed correct operation, close and lock the safe using the normal procedure. |
| Red light on with beeping | The password was not accepted. Keep the door open, press the change switch again and repeat the password-change procedure, then test again. |
Completion beeps during setup and successful entry during testing are separate checks. Always perform the open-door test even if you heard the three completion beeps.
Reference: PDF page 1, sections C–D.
5. Incorrect entries & 3-minute stop
An incorrect password produces three beeps with the red light on.
After three or more incorrect entries, the lock stops operating. Wait 3 minutes, then enter the correct password using the normal sequence:
* Correct password #
If you do not know the current password, contact the purchase store. The manual states that the factory-set master number cannot be changed; it does not provide a customer master-number reset or recovery procedure.
Reference: PDF page 1, section E.
6. Replacing batteries
Low-battery signal
If the red light flashes when you press *, the batteries are running low.
Required batteries
The original manual specifies four 1.5 V alkaline batteries. It does not state their physical size. Match the size marked on the battery compartment or confirm it with the purchase store.
Replacement checklist
- Locate the battery compartment on your safe and check the size and insertion markings.
- Replace the batteries with four new 1.5 V alkaline batteries of the required size, following the compartment markings.
- Check normal operation using *, your current password and #. Where the door is open, complete the check before closing it.
Reference: PDF page 1, section F.
7. Lights, beeps & troubleshooting
| When it happens | Light / sound | Meaning and action |
|---|---|---|
| Pressing * to begin entry | Red light and a beep | Normal start of password entry. Enter your password and press #. |
| Pressing * with low batteries | Red light flashes | Replace the four 1.5 V alkaline batteries. |
| Correct entry, followed by # | Green light | The lock operates. |
| Closing with # | Green light | The lock operates; check that the door is secured. |
| Closing / movement problem | Three beeps at 10-second intervals | Check that the door can close correctly. Avoid forcing it and contact the purchase store if the problem continues. |
| Pressing the change switch | Beep and green light | Enter * → new password → # while the green light is on. |
| Completing a password change | Three beeps | Setup completed. Test the new password with the door open. |
| Open-door password test | Red light with beeping | Test failed. Keep the door open and repeat setup using the change switch. |
| Incorrect password | Red light and three beeps | Entry rejected. Use the correct password; three or more incorrect entries stop operation for 3 minutes. |
| Operation stops after incorrect entries | Lock does not operate | Wait 3 minutes, then enter the correct password. |
Frequently asked questions
Do I need to press * before the password?
Yes. The KC-S opening sequence is * → current password → #. For the unchanged initial setting, use * 123456 #.
How do I lock the safe?
Close the door, press # and check that it is secured. The manual identifies # as the closing command.
Do three beeps always mean the same thing?
No. During password setup they indicate completion. With a red light after an incorrect entry they indicate rejection. During a closing problem, the manual describes three beeps at 10-second intervals. Use the context and light together.
How do I know the new password was saved correctly?
Test * → new password → # while the door is open. A green light means successful entry. If the red light comes on with beeps, repeat the change procedure and test again.
What should I do if I forget the password?
Contact the store where you purchased the safe. The supplied manual does not provide a customer reset or recovery procedure.
Reference: PDF page 1, sections A–F.
8. PDF manual & support
Keep the original KC-S instructions
Download the original one-page English manual for offline reference.
Need assistance?
Contact the store where you purchased the safe if the password is unknown, the lock still does not operate after the waiting period, the door cannot close correctly, or you need help identifying the change switch or battery compartment.
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