Indicators - Dynacord PM 502 User Manual

30 en | Operation
7.9

Indicators

This section describes the indicators at the front panel of the PM 502.
Indicator
SPEAKER PROCESSING
100V DIRECT DRIVE
AMP LIMIT
AMP PROTECT
Table 7.3: Front panel indicators
15-May-14 | 02 | F01U297804
Description
This indicator lights up blue when the internal speaker
processing of the PM 502 is activated in the menu. Please refer
to section Speaker processing (LPN), page 17 for more details
about this mode.
This indicator lights up green when the 100 V Direct Drive
mode is activated in the menu. Please refer to section 100 V
Direct Drive, page 16 for more details about this mode.
This yellow indicator signals that you are operating the PM 502
at the internal power amp's limit. Frequent blinking of the LED
is acceptable, since the amplifier's incorporated clip limiter
prevents distortion. Continuous lighting indicates that you have
to be aware of degradation in the output sound. In that case,
the MASTER (or AUX) level has to be reduced. The LIMIT LED
also lights up if the output level is reduced because of high
amplifier temperature or too high output current in abnormal
load conditions.
This indicator lights up red when one of the PM 502's extensive
protection circuits – against thermal overload, HF-induction,
Back-EMF, DC at the outputs, and short circuit protection – is
activated. When the PM 502 is in protect mode, the speaker
outputs are disabled to prevent the power amp from being
damaged. In this case you should first check whether the
ventilation slots are blocked. Another cause could be that you
have connected more than two 8 Ω speaker systems per power
output in low-Z mode. Please also disconnect the speakON or
Euroblock connectors and check the speaker cables for short
circuits.
User manual
PM 502
Bosch Sicherheitssysteme GmbH