32
PP-32
KOOLMASTER PP-32
REV.01
Tunnel Curtain Controlled by the Static Pressure:
When the pressure drops below the low pressure set point, the tunnel
curtain closes according to a timer. Likewise, when the static pressure
increases above the high pressure set point, the curtain opens according
to another timer. The curtain only starts operating this way once the
start temperature of the first tunnel stage has been reached.
When the curtain starts opening, it first opens during the pre-opening
delay. Fans of the first tunnel stage are then activated.
The following diagram sums up the operation of the tunnel curtain
controlled by the static pressure.
TUNNEL CURTAIN - STATIC PRESSURE MODE
TIME
LOW SET POINT
STATIC
PRESSURE
HIGH SET POINT
STATIC PRESSURE
DROPS BELOW
LO SET POINT:
CURTAIN CLOSES IN
TIMER CYCLE
(CLOSE TIME/ OFF TIME)
CURTAIN STOPS
CLOSING
STATIC PRESSURE
EXCEEDS
HI SET POINT:
CURTAIN OPENS IN
TIMER CYCLE
(OPEN TIME/ OFF TIME)
CURTAIN STOPS
OPENING
CURT
AI
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OP
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N
S
CU
R
T
AI
N
ST
A
Y
S ST
IL
L
CU
R
T
AI
N
CL
O
S
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