The B8512G and B9512G have slots for two B430 Plug-in Telephone Communicators to provide redundant telephone connections.
Upon power up the panel uses the B430 in the Mod-1 slot until a Test Report is initiated or when the panel phone supervision declares the line currently in use as failed.
B430, B8512G, B9512G
Bosch Security Knowledge Base Unable to connect via USB - I have been connecting and programming the panel through the USB connection all day. Bosch Security Knowledge Base Related Products · B3512, B4512, B5512, B3512E, B4512E, B5512E, RPS 5.19, RPS-LITE 5.19, B99
The Standby (Reset) pin is not locked down. The panel 12V backup battery is low or missing. Using the wrong product handler, for example, using 2112 instead of 2212. Too much Current Draw on panel. Disconnect devices from Aux Power and try again. Noise or interference on the keypad Data Bus. Disconnect all wires on the panel data terminals. Not enough free memory in the D5200 Programmer. There should be 60K free memory. Refer to KB article: How to Operate the D5200 Hand Held Programmer. The 2212 handler may be corrupted in the D5200. Delete the 2212 handler and re-download it. Refer to KB article: How to Operate the D5200 Hand Held Programmer. Low batteries in the D5200. Replace batteries using 4 C cells. Trying to program a panel that is not powered up The programming cord is not securely connected to the panel programming port or may be damaged. The DX4010V2 comes with a cord with a 4-pin Molex connector on one end and phone connector on other end. This cable may work as a substitute.