Smart Coin & Cashless Payment Timer
Instruction Manual

INTRODUCTIONCoin and cashless payment, in one box

The Sintron ST-004/ST-005 is an upgraded version of our renowned model, the ST-002/ST-003. Equipped with an LCD and Mobile Payment functionality, it serves as a power timer control for seamless operation. This timer box allows you to effortlessly connect your machine, enabling users to make payments through Apple Pay, Google Pay, Paypal, Venmo, Debit & Credit Cards…(not limited), or Coins. Enjoy the flexibility of setting up time, price, and text displayed on LCD Screen. It is particularly well-suited for 110V~240V Washer & dryers, as well as any machines requiring a timer.

SPECIFICATIONTechnical data

IN THE BOXWhat ships with your unit

• Power cord — supplied with the plug type for your region.
• Hasp kit — a Z hasp with two lock nuts. On the ST-004 and ST-005 the hasp is already fitted to the door. The ST-004-F ships with it as a separate kit, to be installed as required.
• Manual — supplied as a digital copy.

QUICK STARTFirst, identify the parts

1. Plug the power cord into the fused inlet (No. 1), then into a standard household outlet. The LCD (No. 2) should light up and show text.
2. Set up the coin acceptor (No. 3) following Part 1.
3. Set the price and run time using the buttons on the control module (No. 4) following Part 1 and Part 2.
4. Insert a coin. The timer should start counting. If it does not, check steps 2 and 3 again.
5. Power off your machine, then feed its power cord through (No. 5) and into the output socket (No. 6). This may take some force — a snug fit is recommended for safety.
6. Your machine will now run after payment.

What you need to set up

PART 1Coin acceptor and timer settings

💡 Using tokens instead of coins? See token details.

Sintron ST-001 coin setup

The box is equipped with a coin acceptor model: Sintron ST-001, a multi-coin selector that accepts up to 8 different coin types at the same time. This type of selector is widely used in vending machines, massage chairs and other self-service systems.

You will use three buttons on the side of the acceptor: Setup, ADD and MINUS. The two-digit display between ADD and MINUS shows which channel you are on and what value it holds.

Step 1.1 — Coin sampling

Teaching the acceptor which coins to take.

1. In standby, press Setup once. The display shows L1, steady. L1 is the first of the eight coin channels.
2. Prepare at least five coins of the same value (ten is better) and insert them one at a time, ten times in total.
3. After the tenth coin, the display flashes 10 and you will hear a beep. Sampling for that coin is complete.

Step 1.2 — Set the coin value

Telling the unit what each coin is worth.

1. While 10 is flashing, press Setup again to enter value setting.
2. Use ADD and MINUS to set the value. The value is what the coin is worth in your own currency — 0.25 for a quarter, 1 for a one-dollar coin, 2 for a two-dollar coin. A lit decimal point at the bottom right of the display means the value is below 1. See the picture below for an example showing $0.25.
3. Press Setup again to save. L1 (channel 1) is now done — repeat the process for channels L2 to L8 if you have more than one kind of coin.

   PS. If there is a coin you no longer want the machine to accept, set that channel’s value to 0 and it will be rejected.

4. Keep pressing Setup until the display goes dark. The acceptor restarts and beeps — that beep is your confirmation that the settings are stored.

Step 1.3 — Set the price and run time

1. Press SET once. The screen shows the browser setup instructions — that is the other route, described below. To carry on here, press SET again.
2. Timer Setup appears. Use + and − to change the digit you are on, and SET to move to the next digit.
3. When the time is set, keep pressing SET until Coin Amount Setup appears. Set the amount the same way.
4. Press SET once more. The screen repeats back what you set and shows settings saved. You are done.

PART 2The setup page

Locate the three buttons as mentioned from Step 1.3 on the back of the control module (No. 4). Please wear a glove before pressing them.

1. Press SET to enter setup mode. The screen shows the setup instructions.
2. Follow the on-screen instructions to open the settings page in your browser.
3. You will enter the setup page.

Video: enter setup and save

Below are only some of the settings. For the full explanation of all settings, click here.

Page Setting — Wi-Fi and Bluetooth

The top of the setup page holds three things: the device name, which connection the unit uses, and the Wi-Fi details of your own router. You can enable a Wi-Fi connection, Bluetooth for the app, or both.

The setup page as it appears in your browser.

Your Wi-Fi details

You can connect the device to your payment network in two ways:

• Wi-Fi (recommended): If your installation location has internet access, use Wi-Fi. Customers do not need to download any app — they simply scan the QR code and pay.
• Bluetooth / ScanPay App: If there is no internet access at the location, use the ScanPay app via Bluetooth. Download from the Apple App Store or Google Play Store by searching “ScanPay”.

You can also enable both Wi-Fi and Bluetooth if you wish to support both options.

Video: Wi-Fi mobile payment demo Video: ScanPay app demo

Page Settings — Custom LCD text

This is the screen a customer sees before they pay — the billboard, as the product listing calls it. For most customers it is the only instruction they will ever read. You write it yourself, as seven separate lines. Whatever you type goes straight onto the display, top to bottom.

PART 3Payment Gateway Settings (Optional, Need WI-FI internet or Use APP)

Info for you (Owner): the first step is to decide which payment gateway you would like to use, then the second step is to check which payment methods it supports — that is, the ways your customers can actually pay, such as Apple Pay, Google Pay, PayPal, Venmo, or a debit/credit card. Not every gateway supports every method, so this determines what your customers will see at checkout.

Setting Page — Choosing your gateway

A payment gateway is the platform you use to receive money when customers pay with Apple Pay, Google Pay, PayPal, Venmo and so on. Payments go straight into your own account — Sintron does not sit in the middle and does not hold funds.

First decide which gateway you want to use, then check which payment methods it supports.

Fees are set by the payment providers and may change. Check the provider’s own pricing page for current rates. Revolut and myPOS are not listed above — see their own pricing pages.

Part 3-1 — How to set up PayPal

PayPal needs two values on the setup page:

Log in to your PayPal Business account and check that you can manually create an invoice. If you cannot, your account is not yet verified — complete verification before going further.

Video: check if you can create a PayPal invoice

Get your PayPal Client ID and Secret

Video: get Client ID and Secret

Copy and paste the Client ID and Secret into the PayPal fields on the setup page from Part 2.

Then test by pressing the payment button. If the QR code appears, it is working.

Final test

Video: PayPal & coin payment test Video: Apple Pay test

Apple Pay requires an iPhone using the Safari browser. It does not work in Chrome or other browsers.

Part 3-2 — How to set up Stripe

Stripe needs one value on the setup page:

1. Log in to dashboard.stripe.com and click Developer.
2. Click the API Key tab, then Create Secret. You will be asked to verify — choose whichever method you prefer (Touch ID is recommended).
3. Fill in the API name and URL as you wish, for example ST-004 and https://sintron-hk.com. The URL does not matter.
4. You will then get your API key. Copy and save it.

Video: get your Stripe API key

Copy and paste the key into the Stripe field on the setup page from Part 2, then test with the payment button. If the QR code appears, it is working.

💡 Tip: to change the name shown on the payment page, see Video: revise the name

Part 3-3 — How to set up Square

Square needs one value on the setup page:

Before you start, go to Account & Settings and add a Location. If no location is set, Square will block the connection.

1. Add your Location in Square’s Account & Settings.
2. Log in to developer.squareup.com, open the Applications tab and click + to add one.
3. Fill in a name, for example ST-004, and complete the rest.
4. Open the Production tab to see your token.

Video: get your Square API key

Copy and paste the token into the Square field on the setup page from Part 2, then test with the payment button. If the QR code appears, it is working.

Part 3-4 — Revolut and myPOS

Both are supported by the firmware and both have their own fields on the setup page — Revolut asks for one key, myPOS for a pair:

The pattern is the same as the gateways above: create the API credentials in your provider account, then paste them in here and save.

For the current step-by-step guide for these two gateways, contact sales@sintron-hk.com.

PART 4Extra functions

4.1 — Counter and reset buttons

Outside setup mode, two of the three buttons on the back of the control module (No. 4) do this work.

Inside setup mode the same three buttons become +, − and Setup. The board itself is pictured in Step 1.3.

• INQUIRE — press once to read the totals. The screen shows how much money the unit has taken, with coins and cashless payments counted separately.
• CLR — hold for more than 5 seconds, then release. This clears both totals and stops any time currently running.

The figures keep adding up until you clear them, so they are not a daily or monthly figure. Clearing them each time you empty the coin box makes the number read as “since the last collection”. If the unit is online you can have the same totals emailed to you — see Part 2.5.

FIRMWAREOTA update

The unit supports OTA (over-the-air) firmware updates. If you need an update, contact sales@sintron-hk.com.

We also offer B2B services to tailor the functionality to your needs. Get in touch for customisation options.

MAINTENANCEReplacement parts

Something broke? There is no need to replace the whole unit. These components are available separately:

• Solid state relay
• Coin acceptor ST-001
• ST-07 module
• Power cord
• Output socket
• Input socket

Contact sales@sintron-hk.com for availability.

FAQCommon questions

No power after using it for a while?

Usually the fuse has blown to protect the machine. Check the fuse first. Locate the fuse on the ST-004 · Check the fuse on the ST-005. Two spare fuses are included in the box.

Can I use tokens instead of coins?

Yes. The coin acceptor can be trained to accept tokens in the same way as coins. Tokens are available here.

How do I reset the coin acceptor to factory defaults?

Hold the Setup button on the ST-001 coin acceptor for more than 5 seconds. The acceptor resets to factory settings and you will need to train it again with your coin types.

How do I reset the timer to factory defaults?

There is a factory reset at the bottom of the browser setup page. It clears everything you set on that page, so read the warning there first.

Do customers need to install an app?

Not if the unit is on Wi-Fi — they scan the QR code on the screen and pay in their phone browser. The ScanPay app is only needed where the location has no internet and the unit is running over Bluetooth.

Does the machine still work without internet?

Yes. Coin payment runs fully offline with no network and no account. With no internet at the location, customers can still pay by phone through the ScanPay app over Bluetooth.

The coin acceptor is accepting coins it should not accept.

The sensitivity is set too high. Adjust it down until only the correct coin types are accepted. See the sensitivity adjustment video.

How do I extend my warranty?

You can extend it by one year, for two years in total, by submitting the Sintron Warranty Request Form.

What is the difference between the ST-004 and the ST-004-F?

The ST-004-F is front-opening, while the ST-004 is side-opening. Other specs are the same.