Specifications

ST900 Family General Handbook
667/HB/32900/000 Issue 12 Page 62 of 265
detector power supply kit. The maximum number of each type of detector that can
be supported by each power supply is shown in the table below.
HPU
-24V DC 2.8A
667/1/33075/000
-24V DC 50VA / 2.0A
667/1/33074/000
-24V DC 160VA / 6.6A
Siemens ST4R/ST4S
(2.4W / 100mA per detector)
28 20 66
Sarasota MTS36Z or MTS38Z (or any mix)
(3W / 125mA per detector)
22 16 53
Microsense Detectors
(6W / 250mA per detector)
11 8 26
Table 14 – ST900 ELV Detector PSU Selection
The Detector Supply Output from the HPU is routed to a 12-way terminal block on
the side panel of the Cabinet. From this terminal block, power is routed to the
Intelligent Detector Backplanes to power the attached Loop Detector Cards.
Additionally, AGDs may be powered from this supply.
Note
If powering AGDs in addition to Loop Detector Cards from the supplies
above, the current drawn by the AGDs must be taken into consideration
when calculating the number of loop detector cards that can be powered.
Note
Due to the inrush current drawn by the Detector Supply Transformers, there
are limitations to the number of 50VA and 160VA transformers that can be
fitted. Do not exceed the quantities in the table below: e.g. if fitting 2 x
160VA transformers, then a maximum of 3 x 50VA transformers can also be
fitted
667/1/33075/000
-24V DC 50VA / 2.0A
667/1/33074/000
-24V DC 160VA / 6.6A
10 0
6 1
3 2
0 3
Table 15 – ST900 ELV Detector Transformers