C1 Controller Users Manual
Revision 4.6
29
3.1.6
OPTIONAL 4-20mA ANALOG OUTPUT BOARD #10-0167
An optional 10 bit 4-20mA analog output board, shown in Figure 3.7, may be connected
to the I
2
C bus. Each channel’s output will transmit 4mA for 0% readings and 20mA for
100% readings. Loop drive capability depends upon the level of the C1’s primary DC
power supply. With at least 20 volts DC primary power they are capable of driving
20mA through a 750 ohm load. Outputs are self powered and DC power should not be
provided by the receiving device. Note: This PCB requires nominal 24VDC power be
connected to TB2 terminals 1 & 2 as shown in Figure 3.7. Suitable power is available
from the C1 Main I/O board’s TB2 terminal 10 & 12 (see Figure 3.1).
Since the PCB has 8 channels, two are required for 16 channel applications. JP1
configures the outputs for channels groups 1-8 or 9-16.
TB1
Q4
Q6
Q2
Q10
Q12
Q8
D2
Q16
Q14
HI
HI
HI
HI
HI
HI
HI
HI
U11
ST-71 mA OUTPUT BOARD
Q1
LO
LO
LO
LO
LO
LO
LO
LO
Q5
Q3
Q7
PCB # 0010-1121
Assy # 10-0167
C3
High's
Milliamp
Low's
Outputs
Rev 0
CR1
C6
R26
C7
U9
Q13
Q11
Q9
C4
C1
J2
C2
J1
D1
U8
Q15
U10
TP1
Q17
J1 & J2 are interchangable I2C
connectors used to add option
PCB assemblies to the ST-71.
8 Channel 4-20mA Output Option #10-0167
JP1 determines if this 8 channel
Analog Output PCB provides
outputs for CH’s 1-8 or 9-16.
2 PCB assemblies are required
for 16 channels.
Ref. Adj. allows trimming voltage
on TP1. 2.048 volts provides
20mA (+1%) outputs with 100%
of full scale readings.
-
+
Connect to
“DC OUT”
on I/O PCB
24 VDC
INPUT
24 VDC power for output
current loops must be
supplied through TB2.
Connect to main I/O PCB
terminals 10 & 12 of TB2.
TB2
Figure 3.7
Summary of Contents for C1
Page 2: ......
Page 5: ......
Page 39: ...34 Figure 4 2 ...
Page 46: ...C1 Controller Users Manual Revision 4 6 41 Figure 6 3 ...
Page 49: ...44 Figure 6 6 ...