In this failure, module-level devices such as rapid shutdown units or microinverters stop talking to their communication gateway, or never connect to it at commissioning. It shows up as devices that do not respond to detection or that drop communication, and some microinverter systems fall back to a reduced safe output limit when the link is lost. Common causes are devices out of radio range or behind obstructions, wrong termination resistor placement, reversed or loose RS485 wiring, and signal cables run unshielded beside DC cables. Run the gateway test, look for a red LED on the interface board, and measure the gateway supply voltage at both the interface board and the gateway. If short test wiring makes the gateway work, replace the long run with shielded, color-coded cable in the correct wire order. Check the line of sight to each device, add gateways where the signal is weak, and confirm the registered serial numbers match the installed devices. Also check that the gateway is powered and connected to the network, restart the gateway and device, and contact the manufacturer if the problem persists.
affectsc1 drafted · lead MLPE communication gateway
sec=h1 h=8ea1ca213649sec=h1 h=96f9eeb90000tbl=2.r1 h=fccccaa15219tbl=2 h=e2322ffd7706c2 drafted · lead Module-level rapid shutdown device
Tigo TS4-R devices that report through the gateway
c3 drafted · lead Microinverter
tbl=2.r1 h=fccccaa15219tbl=2 h=e2322ffd7706caused_byc4 drafted · lead Weak or obstructed wireless signal
The device may be too far from its gateway, or obstructions may block the RF path between the TS4-R and the gateway.
sec=h1 h=93a1d9e35f6ftbl=85.r2 h=d81335c68816tbl=85 h=556b03932f5fc5 drafted · lead Signal cable electromagnetic interference
Unshielded signal wires run in the same conduit as the DC cables.
c6 drafted · lead Communication bus wiring or termination fault
The termination resistor is misplaced, the RS485 wire order is reversed or cross-connected, or terminals are loose.
c7 verified · fact Installation error
sec=h1 h=8ea1ca213649sec=h1 h=93a1d9e35f6fverified by: review-workflowverified on: 2026-10-24review note: support check: partial - Wiring, resistor and serial-number errors are implied installation faults, but the passages never label them 'installation error'.
c8 drafted · lead Monitoring network configuration fault
The gateway is not connected to the local network.
review note: support check: partial - The Home Manager passages say the gateway is not connected to the local network, but they concern an EM gateway, not the MLPE gateway.
c9 drafted · lead Power supply interruption proposed
The gateway is unplugged, or there is no gateway supply voltage because no AC on the inverter has put the devices into rapid shutdown.
sec=h482 h=e66c10d81a53sec=h1 h=8ea1ca213649presents_asc10 drafted · lead Communication loss
tbl=2.r1 h=fccccaa15219sec=h1 h=8ea1ca213649tbl=85 h=556b03932f5ftbl=85.r5 h=fdfe737743e0c11 verified · fact MLPE detection failure proposed
TS4-R devices do not respond to TS4 detection during commissioning.
sec=h1 h=8ea1ca213649sec=h1 h=93a1d9e35f6fverified by: review-workflowverified on: 2026-10-24
c12 drafted · lead Fallback operation after loss of control or meter signal
Microinverters cut their output current back to a static safe limit once communication has been lost longer than the configured time limit.
tbl=2.r1 h=fccccaa15219tbl=2 h=e2322ffd7706tbl=2.r3 h=9af7a5e8c7a7c13 drafted · lead Red interface board LED proposed
A red LED on the GIB means the termination resistor is installed wrongly or the signal wiring polarity is reversed.
detected_byc14 drafted · lead Communication test proposed
The installation assistant's gateway test returns OK or Warning.
c15 drafted · lead Communication bus voltage test
Measure the supply voltage at the GIB terminal block and at the gateway.
c16 drafted · lead Visual inspection
sec=h1 h=93a1d9e35f6fc17 drafted · lead Known-good component swap test
sec=h1 h=93a1d9e35f6fmitigated_byc18 drafted · lead Communication bus termination and cabling practice
c19 drafted · lead Communication cable check
c20 drafted · lead Proper cable routing
Use shielded, 600 Vdc rated signal cable when it shares conduit with DC cables.
c21 drafted · lead Wireless range extension
Add gateways near the suspect TS4-R locations.
sec=h1 h=93a1d9e35f6fc22 drafted · lead Gateway restart proposed
c23 drafted · lead Complete device configuration
Configure the device for its gateway, and check that the registered serial numbers match the installed devices.
tbl=85 h=556b03932f5ftbl=85.r3 h=369666c4941asec=h1 h=93a1d9e35f6fc24 drafted · lead Network connection check
tbl=85.r4 h=184f99b9bd2ec25 drafted · lead Contact manufacturer service
sec=h1 h=8ea1ca213649tbl=2.r3 h=9af7a5e8c7a7sec=h1 h=93a1d9e35f6f