Bosch PLN-1LA10 Specsheet

Communications Systems | PLN‑1LA10 Plena Loop Amplifier

PLN‑1LA10 Plena Loop Amplifier

www.boschsecurity.com

u High power, current driven amplifier

u Two microphone/line inputs, one priority input

(100 V)

u Selectable frequency range and tone controls

The PLN-1LA10 Loop Amplifier is a cost-effective
amplifier designed to drive a wire loop installed in the
floor or ceiling, covering an area of up to 600 m2 per
amplifier. This solution enables hearing-aid users in
the area enclosed by the wire loop to hear all
announcements, or music. Hearing-aid users can set
their devices to the T‑mode setting to receive the
signal coming from the loop. They receive
announcements in excellent audio‑quality, without the
background noise or reverberations that normally
impair intelligibility for people with hearing
disabilities.

Functions

The loop amplifier can be connected to a mixing
amplifier’s line level output, or it can accept up to two
microphone/line signals directly. A 100 V priority input
is available for uplink to a Plena Voice Alarm System.
This input can be monitored for the presence of a
pilot‑tone. The built‑in supervision monitors all key
functions of the loop amplifier, and the fault state is
available on a fail-safe relay. This makes it possible to
use the loop amplifier in an IEC 60849 compliant
system, and to include the induction loop in the
supervised transmission paths.

u Limiter and automatic gain control (AGC)

u Integrates in an EN 54‑16 and EN 60849 compliant

system

For added ease, the loop amplifier is equipped with a
limiter that keeps the output field strength below the
prescribed 100 mA/m. This circuitry can also be set to
an automatic gain control (AGC) that amplifies weak
signals for enhanced intelligibility, while attenuating
loud signals. This ensures that all information is
presented at a comfortable listening level.

The unit has tone controls and a metal loss
compensation circuit to adjust the sound to the
program material and the environment. The controls
have locks to prevent unwanted access after they have
been adjusted.

The loop amplifier is stackable (master/slave
configuration) to cover very large areas, and supports
low spillover schemes. Its unique quadrate
configuration provides uniform field strengths even
over multiple loops.

Controls and indicators

Front

• LED power meter

• Current meter

• Four LEDS for fault, limiter, AGC, loop integrity

• Headphones socket

• Two tone controls

2 | PLN‑1LA10 Plena Loop Amplifier

• Three input volume controls (master and two
channels)

• On/off switch

Back

• Metal loss compensation control

• Supervision switch

• Voltage selector

• Frequency range switch

• AGC/Limiter switch

• AGC range control

• VOX/mix switch

• Pre/post amp switch

• Two phantom power switches

• Two Mic/line switches

Interconnections

Back

• Master input

• Two slave outputs

• Audio inputs

• Priority input

• Induction loop output

• Line output

• Fault output

• Ground screw

• Mains socket

Certifications and approvals

Safety acc. to EN 60065

Immunity acc. to EN 55103-2

Emission acc. to EN 55103-1

Induction
loop systems

EVAC acc. to EN 60849

Region Certification

Europe CE

acc. to EN 60118-4

acc. to EN 54‑16

Installation/configuration notes

1 Power cord

1 Set of 19” mounting brackets

1 Plena CD

Safety Instructions

Technical specifications

Electrical

Mains power supply

Voltage 230/115 VAC, ±10%, 50/60 Hz

Inrush current 7 A at 230 VAC / 14A at 115 VAC

Max power consumption 500 VA

Performance

Output current 10 A

Frequency response 50 Hz to 10 kHz (+1/-3 dB at -10 dB

ref. rated output)

Distortion <1% at rated output power, 1 kHz

Bass control -8/+8 dB at 100 Hz

Treble control -8/+8 dB at 10 kHz

Mic/line input 2 x

Connector 3-pin XLR, balanced mic/line level

(switchable)

Sensitivity 1 mV / 1 V (mic/line)

Impedance >1 kohm

Dynamic Range 100 dB

S/N (flat at max volume) 75 dB

Headroom 25 dB

Phantom power supply 16 V (switchable)

VOX functionality Input 1 (switchable) mutes input 2

VOX sensitivity -10 dB ref nominal input

PLN‑1LA10 rear view

Parts included

Quantity Component

1 PLN-1LA10 Loop Amplifier

Priority input

Connector Screw

Sensitivity 100 V, transformer balanced

Impedance >100 kohm

S/N (flat at max volume) 63 dB

Headroom 25 dB

Pilot tone detection -20 dB, ref 100 V (10 V)

Pilot tone threshold -26 dB, ref 100 V (5 V)

Master input* 1 x

Connector 1/4" TS jack

Line output