24
C Series
Quick Start Guide
25
Appendix
Maintenance
During normal operation your C Series amplifier will provide trouble-free service. The only user maintenance required is to periodically vacuum clean the foam dust
filters behind the front grille.
In some extreme cases it may be necessary for authorized service personnel to clean the inside of the amplifier. These conditions usually occur after prolonged use in
extreme environments such as those using “cracked oil” smoke machines. If you are using your amplifier in a heavy duty application, it is recommended to have your
amplifier serviced every three years purely as a preventative action.
FAQ
Following are common questions asked about Lab Gruppen C Series power amplifiers together with helpful answers.
Q:
What is the input sensitivity of the amplifiers?
A:
Input sensitivity is calculated from the amplifier gain, maximum output voltage and load. As gain and output voltage are adjustable in C Series amplifiers, you
need to look this information up in a table found in the Appendix section of this manual. Input sensitivity also is automatically calculated in the DeviceControl
software application.
Q:
What are the maximum cable lengths allowed when using the NomadLink network?
A:
NomadLink uses a daisy-chain topology to connect amplifiers and an NLB 60E in a network. Standard RJ45-equipped Cat-5 cables are used throughout. The daisy
chain may be made into a closed-loop by connecting a return cable to the NLB 60E from the last amplifier.
General rules of cable lengths:
• The maximum cable length in between any two devices may not exceed 300 meters / 980 feet.
• In a non-closed-loop daisy-chained subnet the maximum cable length is 400 meters / 1300 feet.
• In a closed-loop subnet the maximum cable length is 700 meters / 2300 feet.
Exceeding these limits may result in lost contact with the devices, or loss of phantom powering due to cable resistance.
Q:
How long can cable-runs be on the Ethernet network connecting the NLB 60E to the PC?
A:
On the Ethernet side, normal Ethernet cable limits apply. This is typically a maximum of 80 meters / 300 feet between each device. Follow standard installation
procedures for Ethernet. Distances beyond 100 meters may require use of a repeater, a format converter, or optical cables.
Q:
Why is the NomadLink network a closed-loop topology?
A:
Technically speaking, the closed loop is optional. The purpose of closing the loop is primarily to provide a secondary path to the amplifiers. If cables are broken or
disconnected in either direction, all amplifiers still may be addressed by the network.
Q:
How can I be sure that no protection circuits or safety functions interfere with the output signal?
A:
If no Clip or Warning LEDs on the front panel light up, you can be fully confident that the rated maximum output power in the full frequency range is available for
your speakers. No limiting or gain-reduction takes place without a warning or fault indication.
Additional documentation
In case you didn’t find what you were looking for in this Operation Manual, check out the website at www.labgruppen.com, where you can find a multitude of
additional documentation for C Series.
Current Draw and Thermal Dissipation Specifications
The following tables contain information on measured current consumption as well as calculated heat dissipation during normal operation (1/8 rated power); and
during extreme heavy duty operation (1/4 rated power).
C 88:4
Level
Load
Rated power
Line Current *2)
Watt *1)
Thermal Dissipation
115 VAC
230 VAC
In
Out
Dissipated
BTU/hr
kCal/hr
Standby with remote power off via NomadLink
0
0
0
0
0
Powered on, idling.
139
0
139
475
120
Amp (I)
Watt
Pink noise
(1/8 rated power)
8 Ω / Ch.
1250 x 4
17.6
8.8
1177
625
552
1884
475
16 Ω / Bridged
2500 x 2
4 Ω / Ch.
2100 x 4
27
13.5
1914
1050
864
2949
743
8 Ω / Bridged
4200 x 2
2 Ω / Ch.
*4)
2200 x 4
33.6
16.8
2221
1150
1071
3655
921
4 Ω / Bridged
*4)
4400 x 2
100 V / Ch.
2000 x 4
26.2
13.1
1838
1000
838
2860
721
200 V / Bridged
N/R
Pink noise
(max power)
*3)
8 Ω / Ch.
1250 x 4
30.0
16.0
2006/2140
1145/1221
860/918
2935/3133
739/789
16 Ω / Bridged
2500 x 2
4 Ω / Ch.
2100 x 4
30.0
16.0
2127/2268
1230/1312
896/956
3058/3263
770/822
8 Ω / Bridged
4200 x 2
2 Ω / Ch.
2300 x 4
30.0
16.0
1983/2115
1016/1084
966/1031
3297/3519
831/886
4 Ω / Bridged
4600 x 2
100 V / Ch.
2000 x 4
30.0
16.0
5992/2236
3467/1294
883/942
3014/3216
759/810
200 V / Bridged
4000 x 2
Mains connector, 230 V CE version
16 A, CEE7
Mains connector, 115 V ETL version
30A Twist Lock
*1) The amplifier’s PSU operates as a non-resistive load, so the calculation “Volts x Amps = Watts” would not be correct. Instead, measured and specified here is what
is known as the “Active Power” in the amplifier providing useful, real-world values of power consumption and heat dissipation.
*2) Current draw figures measured at 230 V. 115 V figures are 230 V figures multiplied by two.
*3) Figures measured at maximum sustainable power without tripping the mains fuse. Listed separately for 30 A/115 V and 16 A/230 V operation. Note that the max.
power condition is very extreme and will not occur during normal operation. Also note that the mains breaker will not be tripped even if operation is
momentarily
in
excess of max. ratings.
*4) Italics used for conditions that, if sustained over long time periods, may trigger the mains breaker. Therefore these measurements should not be used when calculating
cooling requirements as they cannot be sustained by the mains breaker over time.