GAI-Tronics GAI-TRONICS 670-801-EX SmartSeries Manuale - Pagina 10

Sfoglia online o scarica il pdf Manuale per Amplificatore GAI-Tronics GAI-TRONICS 670-801-EX SmartSeries. GAI-Tronics GAI-TRONICS 670-801-EX SmartSeries 17. Smartseries amplifiers for cenelec zone 1 and ul div. 1

Stampa la pagina

Model 670-801-EX and 670-801-UL SmartSeries Amplifiers

Operation

This unit amplifies page audio for broadcast over external speaker(s).

Adjustments

CAUTION

It is necessary to open the explosion-proof enclosure to make adjustments. Make adjustments only

when the conditions at your facility are such that no explosive atmospheres can be present.

This assembly includes one control that permits adjustments to be made while the assembly is mounted in

its enclosure but with the bolted cover removed. In addition there are several internal controls that are

accessible only by removing the assembly from its enclosure.

There is a user adjustment for setting the speaker amplifier gain for the SmartVolume™ feature, which

has three components: Minimum Level, Offset Level, and VLC Level. Although they typically require no

adjustments, these volume levels can be set with the User Level Adjustment control (labeled USER

ADJ). Use a small flat-blade screwdriver with an insulated shaft at least 4 inches long to make

adjustments.

To access the USER ADJ control, perform the following steps:

1. Unbolt and remove the front enclosure cover revealing the speaker amplifier.

2. Loosen (do not remove) the two screws that secure the nameplate.

3. Pivot the nameplate counterclockwise, exposing the access hole.

A guide behind the access hole helps direct the screwdriver to the USER ADJ control.

4. When you are done with the adjustment, pivot the nameplate clockwise into position, then tighten the

two screws. Re-install the bolted cover.

Minimum Level

The Minimum Level adjustment sets the minimum output of the speaker amplifier. The amplifier can be

set from minimum to full output (12 watts into 8 ohms) in 100 discrete steps, or no output. The factory

default is step 20, providing 4 watts.

To adjust the Minimum Level, perform the following steps:

1. Turn USER ADJ fully counterclockwise and wait to hear a single beep over the associated speaker.

This switches the speaker amplifier into the Minimum Level adjustment mode. If there is an audio

signal on the page line when the amplifier enters this mode, you hear it over the associated speaker.

Otherwise, you hear an amplifier-generated test tone.

2. Turn USER ADJ clockwise to the desired minimum speaker volume level.

The amplifier remains in the Minimum Level adjustment mode for as long as USER ADJ is varying.

After USER ADJ has remained stable for five seconds, the amplifier returns to its normal operating

mode.

\\s_eng\gtcproddocs\standard ioms - current release\42004 instr. manuals\42004-615l2.doc

6/97

Pub. 42004-615L2

Page: 10 of 15