Operating Instructions

Laboratory Room Controller Owner's Manual
2-10 Siemens Building Technologies, Inc.
Fume Hood Flow Module
The Fume Hood Flow Module (FFM, P/N 546-00351) collects information about flow rates
from up to four fume hood flows (refer to Figure 2-10). The LRC responds to one fume hood
flow signal. If the LRC is connected to one fume hood, a Fume Hood Controller provides
airflow information. If there are two to four fume hoods, the FFM combines flow signals from
the FHCs and supplies one flow signal to the LRC. The FFM does this by averaging the
voltage signals that are connected to it. This results in a total hood flow signal ONLY if the
incoming signals are scaled the same. The FFM detects open circuit inputs so that it can
correctly average only the signals connected to it, even when a FHC signal fails.
The FFM mounts on a flat surface or to standard DIN rails.
LAB0145R2
546-00351
(S
EL62.19-01)
S
eries A
A
C
24V
+
20%
2.5V
A
50...60H
z
tam
b: 0...50 'C
CE
M
ade in S
w
itzerland
–
Fum
e
Hood
Flow
M
odule
Intended
for
use
w
ith
546-00360
product.
Figure 2-10. Fume Hood Flow Module.