How many Ethernet modules can be extended to the left of AXC F 2152?

Hello I wanted to test that AXC F 2152 could extend several Ethernet modules ,AXC F XT ETH 1TX, but found that after the second module on the left was installed successfully, there was no response to inserting the wire indicator. At present, the power supply is normal. What causes this situation? Thanks a lot!

Hello, At the moment it is only possible to operate the AXC F 2152 with one left-side extension module. - Martin.