User's Manual

Table Of Contents
Cinterion
®
ELS61-AUS Hardware Interface Description
3.2 Power Up/Power Down Scenarios
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ELS61-AUS_HID_v00.031 2016-06-03
Confidential / Preliminary
Page 61 of 102
3.2.5 Automatic Shutdown
Automatic shutdown takes effect if the following event occurs:
ELS61-AUS board is exceeding the critical limits of overtemperature or undertemperature
(see Section 3.2.5.1)
Undervoltage or overvoltage is detected (see Section 3.2.5.2 and Section 3.2.5.3)
The automatic shutdown procedure is equivalent to the power-down initiated with an AT com-
mand, i.e. ELS61-AUS logs off from the network and the software enters a secure state avoid-
ing loss of data.
3.2.5.1 Thermal Shutdown
The board temperature is constantly monitored by an internal NTC resistor located on the PCB.
The values detected by the NTC resistor are measured directly on the board and therefore, are
not fully identical with the ambient temperature.
Each time the board temperature goes out of range or back to normal, ELS61-AUS instantly
displays an alert (if enabled).
URCs indicating the level "1" or "-1" allow the user to take appropriate precautions, such as
protecting the module from exposure to extreme conditions. The presentation of the URCs
depends on the settings selected with the AT^SCTM write command (for details see [1]):
AT^SCTM=1: Presentation of URCs is always enabled.
AT^SCTM=0 (default): Presentation of URCs is enabled during the 2 minute guard period
after start-up of ELS61-AUS. After expiry of the 2 minute guard period, the presentation of
URCs will be disabled, i.e. no URCs with alert levels "1" or ''-1" will be generated.
URCs indicating the level "2" or "-2" are instantly followed by an orderly shutdown. The pre-
sentation of these URCs is always enabled, i.e. they will be output even though the factory
setting AT^SCTM=0 was never changed.
The maximum temperature ratings are stated in Section 3.5. Refer to Table 11 for the associ-
ated URCs.
Table 11: Temperature dependent behavior
Sending temperature alert (2min after ELS61-AUS start-up, otherwise only if URC presentation
enabled)
^SCTM_B: 1 Board close to overtemperature limit.
^SCTM_B: -1 Board close to undertemperature limit.
^SCTM_B: 0 Board back to non-critical temperature range.
Automatic shutdown (URC appears no matter whether or not presentation was enabled)
^SCTM_B: 2 Alert: Board equal or beyond overtemperature limit. ELS61-AUS switches off.
^SCTM_B: -2 Alert: Board equal or below undertemperature limit. ELS61-AUS switches off.