Specifications – Campbell Scientific SDM-SW8A 8-Channel Switch Closure Input Module User Manual
Page 6
SDM-SW8A Switch Closure Input Module
2. Specifications
Operating voltage:
12 VDC nominal (9.6 to 16)
Current drain:
3 mA quiescent, 6 mA active (max)
Environmental:
-25 to +50
o
C, 0 to 90% RH,
noncondensing
Measurement types:
Switch closure (SPDT, SPST) DC voltage
pulse
Input voltage threshold:
From below 0.9 to above 4.0 VDC,±20
VDC max
Maximum input frequency:
100 Hz (50% duty cycle)
Minimum input pulse width:
5 ms high, 5 ms low
Maximum bounce time:
3 ms open without counting
Output options:
State, duty cycle, counts
Max count/port:
65535
Internal sampling frequency:
500 Hz
Watchdog reset:
Yes
Total length of connecting cables: 20 feet
Dimensions:
0.9"(H), 6.2"(L), 2.7"(W)
Weight
0.5 lbs. (0.23 kg)
Compatible dataloggers:
CR10(X), CR800, CR850, CR1000, 21X,
CR23X, CR3000, CR5000, and CR7
TABLE 1. Datalogger to SDM-SW8A Connections
Datalogger
SDM-SW8A
CR7
CR1000,
CR800,
CR850,
CR23X,
CR10(X)
CR3000,
CR5000
21X
+12
(see Note 1)
+12
12 V
12 V
+12
G G
C3 C3 C3 SDM-C3
C3
C2 C2 C2 SDM-C2
C2
C1 IN
C1
C1
SDM-C1
C1
C1 OUT
not used
(see Note 2)
not used
(see Note 2)
not used
(see Note 2)
1H
(see Note 2)
2