Caron Measurement & Controls | www.caroncontrols.net
6
C
HAPTER
3…………………………………T
OP
C
UT
O
PERATION
T
HE
T
OP
C
UT
S
AMPLER ELECTRONICS OPERATE ON ONE
6
VOLT
PC915
ALKALINE BATTERY
.
O
PERATING LIFE OF THE BATTERY VARIES WITH SAMPLING
FREQUENCY
,
BUT WILL GENERALLY LAST
6
TO
18
MONTHS
.
T
HE SAMPLER OPERATES ON A TIME BASED INTERVAL
.
T
HE BUILT IN TIMER IS
TRIGGERED WHEN THE LOOP IS CLOSED ACROSS FLOW SIGNAL INPUT
TERMINALS
(F
LOW SIGNAL OPTIONS LISTED IN SECTION
2.2).
T
HE TIMER IS
RETENTIVE IN
-
BETWEEN CYCLES OF THE FLOW SIGNAL INPUT
.
T
HIS MEANS
THAT IF THE SIGNAL INPUT IS OPENED BEFORE THE TIMER RUNS OUT
,
THE TIMER
WILL PAUSE
,
AND RESUME FROM THE REMAINING TIME THE NEXT TIME THE
INPUT IS CLOSED
.
W
HEN THE FLOW CONDITION INPUT IS CLOSED
,
THE TIMER BEGINS TO COUNT
.
W
HEN THE TIME SETTING IS REACHED
,
THE PULSE VALVE WILL SWITCH ON FOR
2
SECONDS
,
THEN OFF AGAIN FOR
2
SECONDS
,
AT WHICH POINT THE TIMER WILL
RESET AND START COUNTING UNTIL THE INPUT GOES OPEN
.
I
N THE
ON
POSITION
,
THE PULSE VALVE STROKES THE SAMPLE PUMP AND PUSHES THE
SAMPLE FLUID THROUGH THE BACKPRESSURE VALVE AND INTO THE SAMPLE
CONTAINER
.
W
HEN
OFF,
THE PUMP RETURNS TO ITS RESTING POSITION
,
DRAWING ANOTHER SAMPLE FROM THE PROCESS
.
T
HE INTERVAL TIME SETTING IS SELECTABLE FROM THE
8
POSITION SWITCH
INSIDE THE SAMPLER TIMER BOX
.
S
ETTING
0
IS RESERVED FOR THE OFF
POSITION
,
WHILE
1
THROUGH
7
ARE PROGRAMMABLE SET POINTS
.
T
HE SET
POINTS ARE SET UP CUSTOM FOR EACH UNIQUE INSTALLATION AND ARE
MARKED IN SHIPPING HOURS PER DAY
.
T
HE TIMER CHIPS ARE FIELD
REPLACEABLE TO ACCOMMODATE CHANGES IN PROCESS CONDITIONS
.
F
OR
MORE INFORMATION PLEASE CONTACT OUR SUPPORT TEAM
.
T
IME SETTING SHOULD BE SET TO FILL THE SAMPLE CONTAINER WITH
7.2L
OF
FLUID AT THE END OF THE CHOSEN SAMPLE PERIOD
.
A
SAFETY SHUTOFF VALVE
IS USED TO DISABLE THE SAMPLE PUMP WHEN THE SAMPLE CYLINDER REACHES
7.2L.
B
ECAUSE THE SAFETY SHUTOFF USES WEIGHT OF THE SAMPLE CONTAINER
TO GAUGE ITS CONTENTS
,
IT NEEDS TO BE CALIBRATED TO ACTUAL SAMPLE
DENSITY
(S
EE SECTION
3.3.1).
