NRG USER MANUAL
SymphoniePLUS3 User Guide
SymphoniePLUS3_DataLogger_Manual
Rev. 17
support@nrgsystems.com | Page 131
31 December 2018
Is the SIM active? Have you tried the SIM in another phone?
Has the SIM been properly activated for data transfer, and has the SIM been installed into the iPack? Be
sure that the SIM card is activated for transparent data mode.
General GSM System Information
When a GSM phone is powered, it registers with the cellular system, and when it powers down, it de-
registers with the system. The GSM iPack follows this protocol closely.
Using GSM in marginal signal areas can cause registration problems. The iPack de-registers when
powering down. However, if signal is lost, the de-registration is never seen by the cell. The next time the
GSM phone in the iPack is powered up, it will try to register with the system and will be blocked out
because the system thinks it is already registered.
The only solution is to have the central GSM office perform a de-registration and then bring the account
back up. We learned this information by talking with Vodafone and a customer in Europe who
encountered this issue.