TLS-350 Explorer

Chipkin Automation Systems. This tool reads information from your tank gauge console through a serial adapter and produces a report you can send to Chipkin support. It works with Veeder-Root TLS-350 consoles and with the OPW SiteSentinel and other consoles that speak the same protocol. It only ever reads — it cannot change a setting, clear an alarm, or start a test.

version · support reference FSE23204 / #16460

i Before you start

You will need three things:

This laptop, running Google Chrome or Microsoft Edge. Firefox and Safari cannot talk to serial ports.
A USB-to-RS232 adapter, with its driver already installed. Most install themselves when first plugged in.
A serial cable from that adapter to the console’s RS-232 port.

Work down the steps below in order. Each one unlocks the next. The whole process takes a few minutes, and the last step produces two files to email back to Chipkin.

If anything goes wrong, open Troubleshooting at the bottom of this page — it covers the problems people actually hit. If that does not help, the communication log near the bottom records exactly what happened; send it to us and we can usually tell from that alone.

⚙ Wiring and console setup

Pick your console. The serial protocol is the same across these panels; the connector, the settings screen and the indicators are not.

Applies to the OPW SiteSentinel Nano and consoles sharing its board. On this console the RS-232 port is an RJ45 socket, which catches people out when they go looking for a D-connector.

Wiring the RS-232 connection — pinout, colours and the usual mistakes

On this console the RS-232 port is an RJ45 socket, not a D-sub. RS-485 and RS-422 are a separate screw terminal block marked Y, Z, A, B. If the cable is in the terminal block, the RS-232 port is not in use at all.

Three conductors are enough. Transmit and receive must cross over, and the signal ground must be present.

Wire colours below assume the cable is terminated to T568B, which is the common standard. If it was made to T568A, green and orange swap. Always confirm with a meter rather than trusting the colours.

Console RJ45	Cat5 colour	Adapter DB9	Carries
4 TX	blue	2 RXD	Console speaking to you
5 RX	white / blue	3 TXD	You speaking to the console
3 GND	white / green	5 GND	The shared reference both signals are measured against

The most common wiring fault is the ground. White / orange is RJ45 pin 1, which this console uses for RTS, not ground. Landing it on the adapter’s pin 5 ties your ground reference to a signal output on the console. The link may appear to work, then fail intermittently or behave unpredictably, because both ends disagree about where zero volts is. The ground is white / green on pin 3.

A two-wire link using only the blue pair, with no ground at all, often works for years and then turns intermittent. It relies on both devices sharing an earth path through their mains supplies. If you are chasing an intermittent fault on a link that has no signal ground, fit one before looking anywhere else.

What each symptom usually means

What this tool reports	Usual cause in the wiring
Every reply is an exact copy of the request	Transmit is bridged to receive. A loopback plug left fitted, a cable with pins 2 and 3 joined, a breakout board wired wrongly, or an adapter with local echo switched on. Nothing is reaching the console.
No reply at all	Transmit and receive not crossed over, the cable in the RS-485 terminal block rather than the RJ45 socket, or no service mapped to the RS-232 port in the console software.
Replies arrive but are garbled or incomplete	Wrong speed or character format, or a missing signal ground.

Selecting RS-232 in the console software — Preferences, Port Settings

Correct wiring is not enough on its own. The console also has to have a service mapped to the RS-232 port. RS-232 and RS-485 appear as two separate devices, so a service mapped to one is not reachable on the other.

Open Preferences, then Port Settings. The Communications screen appears.
Under Available Services, select the service that should answer this tool.
Under Available Communication Devices, select RS232 Port. The other devices listed are RS485 Port, Modem, FTDI and LAN/WAN.
Click Map.
On the Mapping Configuration popup set Protocol, Baud Rate, Stop Bits, Data Bits and Parity. These must match what you enter in step 3 of this page.
Click Apply.

A mapped service shows a green check and the word configured. View lists the parameters actually in force, which is the quickest way to read the console’s real settings rather than guessing them. Disconnect removes a mapping.

The factory default is 9600 baud, 8 data bits, no parity, 1 stop bit on TLS-350 consoles. If the console has a six-character security code set it will stay completely silent until you enter that code in step 3.

Reading the board LEDs — the fastest way to see what is happening

The main board carries four separate traffic lights: RS232 TX, RS232 RX, RS485 TX and RS485 RX. Watch them while this page is sending requests. They tell you in seconds what a capture takes an afternoon to prove.

RS232 RX	RS232 TX	What it means
flickers	flickers	GOOD The console is hearing you and answering. Any remaining problem is in the settings or the data, not the wiring.
flickers	dark	HEARD, NOT ANSWERING Your request reaches the console and it chooses not to reply. Check the service mapping and protocol above, the device address, and whether a security code is set.
dark	dark	NOTHING ARRIVING Nothing is reaching the console. Check the cable, confirm it is in the RJ45 socket, and check for a loopback. If this tool reports replies while these lights stay dark, the replies are not coming from the console.
RS485 pair flickers instead		The traffic is on the RS-485 terminals, not the RJ45 socket. Either move the cable or map the service to the RS485 Port.

The three status lights nearby are A red for alarm, B yellow for warning and C green for power.

If the console is on RS-485, check jumper P4. The board has three RS-485 jumpers: P2 and P3 choose between RS-485 and RS-422, P5 switches in the 120 ohm termination, and P4 is RS-485 local echo. With P4 set to on, pins 2 and 3, every message is sent straight back and this tool will report that every reply is a copy of the request. Pins 1 and 2 is off. None of these jumpers affect the RS-232 port.

Applies to the TLS-300, TLS-350 and TLS-350R. Source: Veeder-Root Serial Interface Manual, part 576013-635.

Wiring the RS-232 connection — DB25, and why you need a null modem cable

The RS-232 interface is a module reached through a 25-pin D-connector on the bottom left of the console. It is a panel-mount female connector wired as DTE. Your USB adapter is also DTE, so the two transmit pins would otherwise face each other. That is why a null modem cable is required, not a straight-through one. A straight-through cable is for connecting a modem, and it will produce silence here.

Three conductors. The console needs no handshake signals and does not activate any, so RTS, CTS and the rest can be left unconnected.

The pin numbers look like a straight-through cable, but they are not. Both ends are DTE, so pin 2 at the console is an output while pin 2 at the adapter is an input. That is what makes this a crossover.

D-connector pin numbers are usually moulded into the plastic beside the end pins of each row. Check them rather than counting.

Console settings and the security code — front panel and DIP switches

Character format and speed are set from the console’s front panel keypad, not over the serial link.

Setting	What the console allows
Speed	300, 1200, 2400, 4800 or 9600 baud
Data bits	7 or 8
Parity	Odd, even or none
Stop bits	1 or 2
Common default	9600 baud, 8 data bits, no parity, 1 stop bit

Whatever is set here must match what you enter in step 3 of this page.

The security code will make the console appear dead. A four-position DIP switch sits on the CPU board, in the right rear of the console’s printer compartment, next to the battery switch. Position 2 is RS-232 Security Enable. With it on, the console ignores every command that does not carry the correct six-character code, and it answers nothing at all. That looks exactly like an unplugged cable. Enter the code in step 3 if one is set.

The other DIP positions are 1 for front panel setup security, 3 unused, and 4 for fiscal height security. None of them affect whether the port works.

What this console will never do

The interface runs full duplex and, in the manufacturer’s own words, characters are not echoed when received and transmitted characters must not be echoed back to the system. So if this page reports that every reply is an exact copy of the request, the copy is not coming from the console. Look at the cable, the adapter, and anything in line between them.

A command the console does not recognise is answered with 9999 and a checksum, not with silence. Getting that back is a good sign: it means the link works and only the request was wrong.

Applies to the TLS-450 and TLS-450PLUS. Source: Veeder-Root Serial Interface Manual, part 577013-950.

Wiring the RS-232 connection — DB9, and why you need a null modem cable

The RS-232 interface is a module reached through a 9-pin D-connector on the bottom left of the console. It is a panel-mount female connector wired as DTE, the same as your USB adapter, so a null modem cable is required. A straight-through cable is for a modem and will give you silence.

Pins 3 and 2 cross over. Handshake lines are present on the connector but the console neither requires nor activates them.

Full connector pinout

Pin	Signal	Pin	Signal
1	Data Carrier Detect	6	Data Set Ready
2	Received Data	7	Request to Send
3	Transmitted Data	8	Clear to Send
4	Data Terminal Ready	9	Ring Indicator
5	Signal Ground

Check which slot and port you are plugged into. This console takes comm modules in several slots and not all of them can be an RS-232 serial port. Slot 3 port 1 is not available at all, and slot 4 port 2 is for Ethernet devices only. If a port refuses to behave as a serial port, confirm the module is in a slot that supports one.

Console settings and the security code

Set from the console’s front panel.

Setting	What the console allows
Speed	300 through 115200 baud; 9600 is the default
Data bits	7 or 8
Parity	Odd, even or none
Stop bits	1 or 2
Frequent default	9600 baud, 7 data bits, odd parity, 1 stop bit

This console is commonly set to 7 data bits with odd parity, unlike the TLS-350 which is usually 8 with none. If you assume the TLS-350 default here you will get silence or nonsense. If you do not know the setting, use Find settings automatically in step 3.

Changing what a port is used for can reset its speed, data bits, parity and stop bits back to defaults, so check them again after any change.

A six-character RS-232 security code can be enabled here too. With it set and missing from your request, the console stays completely silent.

What this console will never do

As with the TLS-350, the interface is full duplex, characters are not echoed when received, and transmitted characters must not be echoed back. If this page reports that every reply is a copy of the request, something other than the console is producing those copies.

For any other console that speaks the TLS-350 serial protocol. The protocol is the same; only the hardware around it differs. Work through this, then send us what you find and we will fill in the rest.

Finding and wiring the port

Find the serial port. It is usually on the bottom or rear of the console and may be a D-connector, an RJ45 socket or a screw terminal block. If the console has both RS-232 and RS-485, they are normally separate connectors, and only one of them is the one you want.
Work out which end is which. Nearly all of these consoles are wired as DTE, the same as your USB adapter, which means you need a null modem cable that swaps transmit and receive. If a straight-through cable gives you silence, this is the first thing to try.
Connect the signal ground. Three conductors: transmit, receive and ground. A link with no ground may work for years on a shared earth path and then turn intermittent for no apparent reason.
Leave the handshake lines alone. These consoles generally neither require nor activate RTS, CTS or the modem control signals.

If the console has an RS-485 port and it is in half duplex, every message you send comes back to you as a copy of itself. That is normal for that wiring, not a fault, but this page will report it as a loopback. Use the RS-232 port if there is one.

Settings to look for

Setting	Usual range
Speed	300 to 9600 on older consoles, up to 115200 on newer ones
Data bits	7 or 8
Parity	Odd, even or none
Stop bits	1 or 2

If you do not know them, do not guess. Use Find settings automatically in step 3, which tries each combination in turn.

Check for a security code before assuming the port is dead. Consoles in this family answer nothing at all when a six-character RS-232 security code is set and your request does not carry it. Silence does not mean broken.

Quick checks that narrow it down fast

Traffic lights on the board. Many consoles have separate transmit and receive indicators. If the receive light flickers when this page sends a request, your wiring is good and the problem is elsewhere. If it never flickers, nothing is arriving.
Unplug at the console end. Leave the adapter connected and run a read. Replies that keep arriving with the console disconnected are being produced by the cable or the adapter, not the console.
Check for a bridge between transmit and receive. A loopback plug left fitted, or a cable with those two pins joined, makes every request come back as a perfect copy of itself.

1 Environment check

Runs automatically. Nothing to click.

2 Choose the serial adapter

Click below, then pick your USB-to-RS232 adapter from the list the browser shows. An empty list means the adapter is unplugged or its driver is not installed.

3 Connection settings

If you know the console's serial settings, enter them and press Connect. If you do not, use Find settings automatically below.

Baud rate

Data bits

Parity

Stop bits

Security code

Timeout (ms)

Find settings automatically — if you do not know them

Tries each combination of speed and character format, asking the console for its status each time. Disconnect first if you are connected. Keep this tab in front while it runs — browsers deliberately slow down background tabs, which makes the search take much longer.

How thorough

On success

4 Read the console

This asks the console for everything it will tell us, one report at a time. It takes about half a minute.

Or watch the console continuously. Tanks, sensors and alarms refresh on every cycle, so changes at the site show up as they happen.

Refresh every Read each cycle

Send a single report request instead

5 Reproduce the gateway

This is the most important step for diagnosing your fault. The gateway does not read the console once — it asks the same few questions over and over, for as long as it is running. Your gateway fails about 17 seconds after the console is connected, which suggests the problem only appears after it has been asking for a while. Reading everything once, as in the step above, may never trigger it.

This repeats exactly what your gateway does: the same requests, to the same devices, at the same rate, continuously. Let it run for at least a couple of minutes — well past the point where the gateway normally fails.

Number of tanks

Status request every

Tank request every

Run for

6 Console report

● Communication log

Waiting…

show text alongside hex hide byte detail

7 Send the results to Chipkin

Download both files and email them to your Chipkin contact.

If you entered a security code, note that it forms part of every request sent to the console, so it appears in both files. Tell us if that is a problem and we will work around it.

Capture format

If downloads are blocked, copy the report from here instead

Going somewhere without internet? Save this tool to the laptop and open it from there later. It is a single file and needs no installation, no network and no administrator rights.

? Troubleshooting

Step 1 says this browser cannot talk to serial ports

Only Chrome and Edge can. If you are already in one of those, the feature has most likely been switched off by your organisation’s IT policy. Send your Chipkin contact a screenshot of the step 1 box — it names the browser and the exact reason, and IT can allow serial access for this page specifically without giving you administrator rights.

If it says not running in a secure context, you opened a copy of the file from somewhere the browser does not trust. Use the link Chipkin sent you, or use Save this tool for offline use in step 6 to get a copy that works locally.

The list of serial ports is empty

The adapter is not plugged in, or Windows has not installed its driver. Unplug it, plug it back in, wait a few seconds and try again. To confirm Windows can see it at all, open Device Manager and look under Ports (COM & LPT) — the adapter should appear there with a COM number. If it appears with a warning triangle, the driver needs installing; the adapter’s manufacturer supplies it.

“Could not open the port”

Something else is holding it. Close any terminal program, any other tab running this tool, and any vendor configuration software, then try again. If you have just finished an automatic settings search, give it a couple of seconds — the previous version of this tool could leave the port open, which is fixed in version 3.0.0.

No reply from the console

Work through these in order:

Settings. Use Find settings automatically in step 3. If nothing is found on any combination, the cause is one of the next three.
Cable. The console’s transmit line must reach the adapter’s receive line. A straight-through cable where a null-modem cable is needed will look exactly like a dead console.
The console’s own port. Check on the console’s front panel that its RS-232 port is enabled and note the speed and character format it is set to.
A security code. This one is important and not obvious: a console with a security code set stays completely silent when the code is missing. It does not complain, it simply says nothing — which looks identical to an unplugged cable. If the console has a six-character RS-232 security code, enter it in step 3.
The console’s port mapping. Correct wiring is not enough. A service has to be mapped to the RS-232 port in the console software. See Wiring and console setup near the top of this page.

Every reply is a copy of the request

The tool reports this as REFLECTED_COMMAND, and as a loopback when it happens on every request. It means the bytes the adapter sent out came straight back in, byte for byte. A console never does that — its replies start with the same function code but carry data and a checksum. Something between the adapter and the console is joining transmit to receive: a loopback test plug left on the adapter, a cable or terminal block with TX and RX bridged, a null-modem adapter stacked on a null-modem cable, or a serial adapter with local echo switched on. The console has not been heard at all, so nothing in the report describes it. Fix the cable first; the settings search cannot help until then.

Open Wiring and console setup near the top of this page for the RS-232 pinout, the wire colours, and how to read the console’s own transmit and receive lights — those lights settle in seconds whether anything is reaching the console at all.

A reply that starts with a copy of the request and then continues with the console’s answer is different. That is a half-duplex RS-485 adapter hearing its own transmission, which is normal for that hardware. The tool notes it as ECHOED_COMMAND, removes the echo, and analyses the answer that follows as usual.

Replies arrive but look like nonsense

That usually means the speed is right but the character format is not. The automatic search reports this as tier 3 or 4 and it is genuinely useful: it means the baud rate is correct, and only the data bits, parity or stop bits need changing. Try the other formats at that same speed, or run the exhaustive search.

The report shows problems — is the tool broken?

Almost certainly not. Finding problems is what this tool is for. The console at this site returns something a gateway driver does not expect, and the anomaly list is how we identify what. A report full of anomalies is a useful report. Please send it.

Equally, a report with no anomalies at all is also a useful result — it tells us to look at timing or wiring instead of at the data.

Nothing downloads when I click the buttons

Some managed machines block downloads. Every download button has a fallback: expand If downloads are blocked, copy the report from here instead in step 7, press Copy to clipboard, and paste the result into an email.

It seems to have stopped part-way through

Check the tab is in front. Browsers deliberately slow down tabs running in the background, which can make a search that normally takes two minutes take considerably longer. Nothing is lost — it is only slower. Bring the tab to the front and it speeds back up.

If it is genuinely stuck, no step waits more than about six seconds before giving up and moving on, and the communication log will name the step that failed.

Could this change anything on the console?

No. The tool holds a fixed list of read-only report requests and refuses to send anything else — not behind a setting, not behind a hidden option. It cannot change a configuration, acknowledge or clear an alarm, or start a leak test. Every byte it sends is recorded in the communication log if you want to check.