Problem Details
A Stride SIO-MB16ND3 Modbus TCP discrete input module is powered and cabled directly to a laptop, but the browser returns "site can't be reached" when pointed at the documented default address http://192.168.1.100. No configuration has been performed yet, so the module should still be at factory defaults.
Two failure classes produce this exact symptom, and they are indistinguishable from the browser alone:
| Failure class | Description | Confirming evidence |
|---|---|---|
| Module is not at defaults | The unit was previously commissioned (by an integrator, a bench test, or a prior project) and holds a static IP outside 192.168.1.0/24 | PWR/STS LEDs normal, link LED on, but no ARP reply or ping response at .100 |
| PC-side reachability | The NIC is on a different subnet (DHCP/APIPA 169.254.x.x, or a corporate 10.x/172.x address), or Windows is routing the request out a different adapter (Wi-Fi, VPN, Hyper-V vSwitch) | Module answers on a different PC or on a switch with a known-good laptop |
Root Cause
The Stride field remote I/O module serves its configuration web server only on its own IP address, and it does not act as a DHCP client or server. Reaching it requires a Layer 3 path that exists entirely inside the module's own subnet:
- The module's IP must actually be
192.168.1.100(or whatever value it currently holds). - The PC NIC must carry an address in the same subnet, e.g.
192.168.1.10 / 255.255.255.0. - The operating system must select that NIC for the destination, which requires no competing route and no VPN default-route capture.
If any one of the three conditions fails, the TCP SYN to port 80 is never delivered and the browser reports an unreachable site rather than an HTTP error. There is no partial-success state, so treat this as a binary connectivity problem and prove each layer independently.
Solution: Reset the Module to Factory Defaults
If you cannot confirm the module's current IP, force it back to a known state before troubleshooting the PC.
- Apply power to the module and confirm the green
PWRLED is on. - Confirm the module is not in INIT mode. The reset procedure is performed with the device powered and out of INIT mode.
- Press and hold the
RESETbutton on the front of the module for 5 seconds. - Observe the LED sequence: the green
PWRLED switches off and the yellowSTSLED turns orange while the reset executes. - Release the button and wait for both LEDs to return to their default condition. That indicates the reset is complete.
After a successful reset the module holds these values:
| Parameter | Default value |
|---|---|
| IP Address | 192.168.1.100 |
| Subnet Mask | 255.255.255.0 |
| Default Gateway | 192.168.1.1 |
| Modbus Address (Unit ID) | 1 |
| Web Username | admin |
| Password | password |
192.168.1.100 is not already assigned to another device before the module rejoins the segment.Solution: Configure the PC Side
Once the module is known to be at 192.168.1.100/24, force the laptop onto the same subnet and eliminate competing adapters.
- Simplify the physical path. Connect the module directly to the PC's Ethernet port, or through a single unmanaged switch with nothing else attached. Remove the module from the plant network for commissioning.
-
Disable every other NIC. In
ncpa.cpl, disable Wi-Fi, VPN adapters, Hyper-V virtual switches, WSL, and any USB/docking-station NIC you are not using. This is the single most effective step on Windows 11. -
Set a static IPv4 address on the wired NIC:
IP address: 192.168.1.10Subnet mask: 255.255.255.0Default gateway: (leave blank)DNS: (leave blank)
Leaving the gateway blank prevents Windows from installing a second default route that competes with your normal network. -
Verify addresses are unique. Do not use
192.168.1.100or192.168.1.1for the PC. Any address in .2-.99 or .101-.254 that is not already in use is fine. -
Browse to
http://192.168.1.100and log in withadmin/password.
Verification and Diagnostics
Work bottom-up. Do not move to the next layer until the current one passes.
| Layer | Test | Pass criteria | If it fails |
|---|---|---|---|
| Power | Observe front-panel LEDs | Green PWR on, STS in default condition | Check field power wiring and supply voltage at the terminals |
| Link (L1) | Ethernet port link LED on both module and PC | Link LED lit on both ends | Swap patch cable; try a straight-through and a known-good cable; try a switch instead of direct connection |
| PC address (L3) | ipconfig /all |
Wired NIC shows 192.168.1.x / 255.255.255.0, not 169.254.x.x | Static assignment did not apply; disable/re-enable the adapter |
| Reachability | ping 192.168.1.100 |
Replies received | Module is not at .100 or is on another adapter's path |
| Address discovery |
arp -a after the ping attempt |
MAC address listed against 192.168.1.100 | Incomplete entry means no device answered ARP; perform the RESET procedure |
| Routing |
route print or Test-NetConnection 192.168.1.100 -Port 80
|
Traffic to 192.168.1.0/24 uses the wired NIC interface index | Disable the competing adapter or VPN client |
| Web server (L7) | Test-NetConnection 192.168.1.100 -Port 80 |
TcpTestSucceeded : True | Ping OK but port closed indicates a browser/proxy issue, not a network issue |
Browser-Side Gotchas
- Type the full
http://192.168.1.100. Modern browsers default to HTTPS and a plain192.168.1.100entry may be rewritten tohttps://, which the module's HTTP server will not answer. - Disable any system or browser proxy for local addresses. A corporate PAC file will send the request to a proxy that cannot route to a point-to-point link.
- Test with a second browser or a private window to rule out cached HSTS/redirect entries.
- Windows Defender Firewall does not normally block outbound HTTP, but if the wired NIC is classified as a Public network, third-party endpoint security may block traffic. Set the adapter to Private for commissioning.
Post-Commissioning Checklist
After you regain web access, complete the configuration before returning the module to the machine network:
- Assign the production IP address, subnet mask, and gateway that match the plant addressing plan.
- Change the default
admin/passwordcredentials. Leaving factory credentials on a networked I/O module is an unnecessary exposure. - Set the Modbus Unit ID if the default of
1conflicts with another device behind the same gateway or master. - Record the final IP, Unit ID, register/coil map, and credentials in the panel documentation. The next person to open the enclosure should not have to press RESET.
- Return the PC NIC to DHCP, re-enable the disabled adapters, and confirm the module responds from the PLC or Modbus master at its new address.
- Confirm the discrete input mapping with a Modbus poll utility: read the input status registers and toggle a field device to verify bit alignment before commissioning logic.
FAQ
How do I reset a Stride SIO-MB16ND3 to factory defaults?
With the module powered and not in INIT mode, press and hold the front-panel RESET button for 5 seconds. The green PWR LED turns off and the yellow STS LED turns orange during the reset; when both LEDs return to their default condition, the module is back at 192.168.1.100 / 255.255.255.0, gateway 192.168.1.1, Modbus address 1, admin/password.
What is the default IP address and login for the Stride SIO module web server?
IP address 192.168.1.100 with subnet mask 255.255.255.0 and gateway 192.168.1.1. The web login is username admin, password password. Change the password once you have access.
Why can't I reach 192.168.1.100 from my Windows 11 laptop?
Usually the NIC is not on the 192.168.1.x subnet, or Windows is sending the request out Wi-Fi, a VPN, or a Hyper-V virtual adapter. Set a static 192.168.1.10 / 255.255.255.0 address on the wired NIC with a blank gateway, and disable every other network adapter in ncpa.cpl.
How do I confirm the module is actually on the network before blaming the browser?
Run ping 192.168.1.100, then arp -a. A MAC address listed against 192.168.1.100 proves the module answered ARP at Layer 2/3. Then run Test-NetConnection 192.168.1.100 -Port 80; TcpTestSucceeded : True means the web server is up and the fault is browser or proxy related.
Will resetting the module erase my Modbus configuration?
Yes. The reset restores all listed defaults, including the Modbus address (back to 1) and the credentials, not just the IP settings. Document the existing configuration before pressing RESET on an installed module.