| 3 Important safeguards Before you install or operate the Plena Loop Amplifier, you must read the Important Safety Instructions. The Important Safety Instructions are supplied together with the Plena Loop Amplifier. Bosch Security Systems | 2005-05 | 9922 141 50672en...
Bosch Security Systems thanks the NVVS (Dutch Association of Hard of Hearing People) for the valuable information that was provided during the development of the Plena Loop Amplifier and the creation of the Installation and User Instructions. Bosch Security Systems | 2005-05 | 9922 141 50672en...
Note • Warning General sign for notes. If you do not obey the warning, you can cause personal injury or death. Note Refer to another information source. Bosch Security Systems | 2005-05 | 9922 141 50672...
PC call stations, an ‘All-in-One’ system and a voice alarm system. Each element is designed to complement all others thanks to matched acoustical, electrical and mechanical specifications. Bosch Security Systems | 2005-05 | 9922 141 50672en...
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1.3: Front and rear views Priority 100V input Master in Phantom Bal. input Master Tone 0º Line Priority Limiter control 90º Slave out Bal. input Mute Line 90º 0º figure 1.4: Block diagram Bosch Security Systems | 2005-05 | 9922 141 50672en...
(refer to section 6.1 and section 6.2). control (AGC) or the limiter (refer to section 5.7.2). 25 AGC range control - Controls the range of the automatic gain control (see section 5.7.3). Bosch Security Systems | 2005-05 | 9922 141 50672en...
Amplifiers work together to make a magnetic field that has the same strength throughout the whole covered area drops fast to zero beyond the borders of the covered area. figure 2. 1 : Simple system, single loop Bosch Security Systems | 2005-05 | 9922 141 50672en...
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Although it is not required, the sizes of the master and slave induction loops are typically the same. 0° 0° 90° 90° 0° 90° figure 2.3: Simple system, single loops figure 2.4: Simple system, multiple loops Bosch Security Systems | 2005-05 | 9922 141 50672en...
50 and 66% of the width of the the same. master induction loops. 0° 50-66%W 0° 90° 90° 0° 0° 90° 50-66%W 90° figure 2.6: Low-spill system (example) figure 2.5: Expanded system (example) Bosch Security Systems | 2005-05 | 9922 141 50672en...
The numbers next to the curves show the distance from the floor to the induction loop in % of the width (W) of the room. Bosch Security Systems | 2005-05 | 9922 141 50672en...
2.4.3 Earth loops Earth loops can cause interference on the induction loop system. You can avoid earth loops when you connect the shielding of cables only to one device. Bosch Security Systems | 2005-05 | 9922 141 50672en...
(refer to figure 3.1). 0 dB -6 dB -2 0 dB Po we Cu rre Ma ste Fa ult Lo op Int eg rity AG C Lim ite figure 3. 1 : Installation Bosch Security Systems | 2005-05 | 9922 141 50672en...
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Plena Loop Amplifier | Installation and User Instructions | Installation en | 20 Intentionally left blank. Bosch Security Systems | 2005-05 | 9922 141 50672en...
63 dB @ max. volume 220 to 240 V(AC) 75 dB @ min. volume/mute Headroom: 25 dB Note The PLN-1LA10 Loop Amplifier is delivered with the voltage selector in the 230 position. Bosch Security Systems | 2005-05 | 9922 141 50672en...
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400 W Mains inrush current: max. 7 A @ 230 V(AC), max. 14 A @ 115 V(AC) Signal-to-noise ratio: 63 dB @ max. volume 75 dB @ min. volume/mute Headroom: 25 dB Bosch Security Systems | 2005-05 | 9922 141 50672en...
Phant Phant Line fuse Line fuse : 230 V 3A : 230 V 3A Phant 115V Phant 115V Line Loop Line Loop Line Line figure 4.8: Master and slave loop amplifiers Bosch Security Systems | 2005-05 | 9922 141 50672en...
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Plena Loop Amplifier | Installation and User Instructions | External Connections en | 26 Intentionally left blank. Bosch Security Systems | 2005-05 | 9922 141 50672en...
9 Switch off the master loop amplifier with the power switch on the front. 10 When the induction loop system contains slave loop amplifiers, configure the electric current through the slave induction loops (refer to section 5.2.2). Bosch Security Systems | 2005-05 | 9922 141 50672en...
Do not forget to re-connect all induction loops 5 Repeat the procedure for the other loop amplifiers in after you have configured the electric current the induction loop system. through the induction loop of the last loop amplifier. Bosch Security Systems | 2005-05 | 9922 141 50672en...
Priority input volume control. The Priority input volume control is on the rear of the loop amplifier (refer figure 5.5: AGC/Limiter switch to figure 5.4). Priority input Limiter 5K 10K 100V figure 5.4: Priority input volume control Bosch Security Systems | 2005-05 | 9922 141 50672en...
Phantom switch in the OFF position. Limiter 5K 10K figure 5.7: Frequency range switch Phantom Line figure 5.9: Phantom switch Bosch Security Systems | 2005-05 | 9922 141 50672en...
To switch Vox off, set the Vox/Mix switch in the Mix position. The audio signal of audio input 1 and the audio signal of audio input 2 are mixed. Phantom Line figure 5. 1 0: Vox/Mix switch Bosch Security Systems | 2005-05 | 9922 141 50672en...
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Plena Loop Amplifier | Installation and User Instructions | Configuration en | 32 Intentionally left blank. Bosch Security Systems | 2005-05 | 9922 141 50672en...
The Power switch is on the front of the loop amplifier (refer to figure 6.1). The green power LED on the front of the loop amplifier (refer to figure 6.2) goes off. Bosch Security Systems | 2005-05 | 9922 141 50672en...
Check which input is too Refer to section 5.7. of the inputs is clipped off loud and turn its volume because it is too strong. control counterclockwise to decrease the volume. Bosch Security Systems | 2005-05 | 9922 141 50672en...