AUDIO TELEX ACM2150 User manual

AMrilDiltil@ tHl-ill
c
o
-
.f-,
()
=
f-
a
g
c
(I
.f-,
ru
l-
o
CO M M U N I CATI O N S;rlrL:rD
ACM2150
Dual Channel
Power Amplifier
A
A,5TFAIAN MTOC 3
(l*,
Et&rld
ConprV
ctat|!
IIEIS
Audio Telex Gommunications pty Ltd
ACN 001345482 hcorporated tn NSW
NSW & ACT QLD & NT vlc
149 Beaconsfleld Street
Prlvate Bag 149
Sllverwater NSW 2128
Australla
Ph 02 9047141',
Fax [phone]
42 Commerclal Road
PO Box 871
Fortltude Valley QLD 4006
Ph 07 3852 1312
Fax [phone]
2U277 tlddleboriugh Road
Box Hlll VIC 3128
PO Box lSi
Blackburn South VIC glg0
Ph 03 98907477
Fax [phone]
WA SA TAS
7164-66 Kent Street
PO Box 489
Cannlngton WA 6107
Ph 08 9356 2761
Fax [phone]
Electronlc Concepts pty Ltd
76 George Street
Thebarton SA 50gl
PO Box 7030 Hutt Street
Adelalde SA 5000
Ph 08 82349444
Fax 08 8234-%lt
K W l{cCulloch Pty Ltd
54a Albert Road
lloonahTA8 7009
Ph 03 6228 e,?,73
Fax [phone]
New
Unlt B, 11 Plermark Drlve
PO Box 512
Albany NZ '1331
Ph 09 415 9426
Fax [phone]

ACM21 50
150 + 150 Watt Power Amplifier
Product Description
The ACM2l50 is a dual channel 150 + 150 watt power amplifier in a two rack unit (2RLf chassis suitable for table or direct 19"
rack mounting. The ACM2I50 has outputs for 100 volt line or 4 - 8 ohms and has an active balanced input of lOK ohms. The
ACM2I50 will operate llom 240 VAC @ 50 Hz or ll0 VAC @ 60 Hz (not user selectable, internal factory adjustment only,
specifo at the time of ordering). The ACM2I50 also features auto-sensing fan cooling and over temperature protection. The
maximum recommended load for the ACM2l50 is 65 ohms per channel for 100 volt line operation and 4 ohms per channel for
low impedance operation.
Front Panel Controls
OUtpUt Level: The input level controls are unlabelled, recessed (screwdriver adjustable) and are located in the centre of
the front panel. Turning a control clockwise will increase the output of the particular channel of the ACM2I50 towards it's
maximum output level while turning the control counter-clockwise will decrease the output level. Adjust this conkol for the
desired output level depending on the level of the input signal (from a mixer or other sigrral source). The factory default setting
for this control is I volt input will supply full load into 4 ohms.
POWef SWitCh: The rocker switch located in the front centre of the panel turns AC power on to the ACM2I50. Rocking
the power switch to the right to turns the AC power 'on'. When the AC power is 'on', the "CH A" and *CH B" LED's will glow
in the amplifier status display window.
Cooling Fans (Air lntake): tre cooling fan is temperature sensitive and will only switch on when the temperature
of the ACM2150 had reached a pre-determined range. The fan will stay on and only switch offagain once the ternperature of the
amplifier has fallen below a pre-determined level. So, the fact that the fan is not operating at any time (and most noticeably to the
operator at turn-on) does not mean that the amplifier is faulty in any way, just that it is operating within a temperature range that
does not need fan cooling for adequate heat dissipation. If the ACM2I50 is operating continually at conservative levels and
proper load conditions, it is possible that the cooling fan will not switch on at any time during normal operation. Whan operating,
the fans cause air flow from the front to the rear of the amplifier.

Amplifier Status Display Window
The status display window highlights the operating conditions of the ACM2l50.
F-F
ll
()(4
-, I I I I I I I I I
lll l 2r ra rJ t2 9 6 5 O tt
l{[I1 TIIP TAULT
-- I I I I I T I T I
Ul! 2l 16 t5 t2 9 G| 5 O +t
l. Channel A / Channel B: These LED's glow green if AC power is switched on to the ACM2l50.
High Temperature: This red LED glows if the fans have failed and the amplifier has been shut down by its,
temperature control circuitry. If this LED is glowing and the fans have not failed, it means that the amplifier is operating in
an ambient environment that is naturally too hot for fan cooling to make any difference to the temperature of the amplifier.
3. Fault: This LED glows red if there is DC present on the ourput (speaker lines) in which case the speakers will be
internally disconnected from the amplifier stage.
4- Output Level VU MeteIl Two 9 segment LED VU meters are provided to give an indication of the output signal
levels of each channelof the ACM2I50 from -21 to +3 dB. For normal operation the LED's should oscillate in and out of
the red zone' If the LED's in the red zone are lit continually, then the output level control (or the level of the input signal to
the ACM2I50) should be adjusted to reduce the ouput level. Too much output level can cause distortion and possible
damage to the connected speaker system.
Rear Panel Connections
l' 3 Pin lEC, AC Mains Power lnlet The operating voltage is 240 VAC @ so rlzor n0 VAc @ 60 FIz. The
AC power voltage level is not externally user selectable but is factory prsset (via transformer selection).-Ttt" ittl"t i,
equipped with an inbuilt AC fuse holder fitted with a 6 Amp slow blow frse plus one spare fiue. power consumption is 300
VA. Please ensure that the mains power cord is disconnected before attempting to check or replace this fuse.
qaQ"a !-::::.'.::::-::
r---:--r-:
r::::-_:(:=
-)--
(-_=t:l-l
FE'Egtnq
l.< -r .* -nl
a"gQ"g
:
G-
c-
-)
Continued ouo p"g" $

2. Output Selector Switch: This selector slide switch is used to select the output level desired. Before adjustir
this switch in any way please make sure that the AC power switch is in the "off'position. Any selection made is common
both channels and they cannot be selected independently of each other. To select an output oi 100 volts RMS (100 volt lir
or high impedance) move the switch to the left position when looking directly at the iear of the amplifier. To select r
output of 4-8 ohms (low impedance) move the switch to the right position whar looking directly at the rear of the amplifie
Note: If the incorrect setting is used this may cause serious damage to the amplifier and/or speakers and void ar
warranQr claim. Refer to your authorised dealer or Audio Telex for further information.
Output Terminal Strip: Reading from left to right these connections are as follows:
Positive connection for channel B output
Negative connection for channel B output
Spare
Spare
Positive connection for channel A output
Negative connection for channel A output
Note: These outputs (channels A & B) cannot be selected or wired for bridged mode mono operation.
DC Low Voltage Fuse Receptacles: Access the DC fuses by turning the caps half a turn counte
clockwise with a screwdriver. The value of the fuses is 5 Amps slow blow. Please ensure in"t tn" AC power switch is i
the 'off position and that the mains power cord is disconnected before attempting to check o" ""pla"" any of ther
fuses.
lnput (& Parallel Output) XLR Signal Connections: The inputs (A & B) to the ACM2I50 ar
active balanced @ lOK ohms. The pin configuration of all sockets is as follows: pin #l-earth ; pn #2-active (high, +); pi
#3-active (low, -). The output socket is to allow the original input signal to be fed on to another amplifier. As-these t\r
sockets are wired in passive parallel for each channel, the failure of any one amplifier will not affect the signal flowin
through that amplifier to another amplifier.
3.
4.
Fuse Sizes ACltl2150 Amplifier
tiains 240 VACI 6AmperesStowBlow
DG: 5 Amperes Slow Blow
Looking for something worthy to connect to the inputs and outputs of your neu
ACtl2150? Well, please call your nearest Audio Telex Communications office for
referral to your closest authorised Dealer or for more information on the ful
selection of our compatible sound system products.