Using old 540S Ambient Sensors w/ T9032NS, T9040NLR or DNA Amp

This articles applies to very old installations that want to upgrade to Titan digital network technology.

The T9032NS can support up to 32 of the newer model 540S ambient noise sensors, which draw 3ma each.  Sensors made before 12/12/1986 draw three times as much current, 9ma.  When retro-fitting old installations, the installer should be aware that the T9032NS should only be configured with a maximum of 15 of these older sensors.

The raw numbers are:

  • T9032NS can support 150ma at 27V
  • Old 540S draws 9ma
  • New 540S draws 3ma

[8/8/16 KATench Update]:  The same power supply exists on the T9040NLR and DNA78xx and DNA24xx 4-channel power amplifiers.  This means the DNA amps can accept all 8 sensors as either old or new type and the T9040NLR can accept almost all of its sensors as the old type (15 out of 16).  

[4/6/18 KATench Update]: The T112 has been tested as having sufficient power to handle up to 23 old style sensors (almost all 24 positions).  Measurements were that the supply held at near 27V (dropping to 25.68V) with a 5.7 Watt load (or 211 mA at 27V).

[10/7/24 CDeatrick update]: The T112 that was tested in 2018 was done past the specification of the power supply. There is around 72mA of headroom in the design of the T112, allowing for 8 old 540S on a T112 (72/9mA=8). The ZOP has a similar power design therefore can handle all eight old 540s.