AccuEnergy AcuDC 241, User Manual

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circuit (the last meter of the chain) if the communication quality is distorted.

If a RS485 converter is used, it should support optical isolation and surge protection.
Digital Input
AcuDC 240 optional I/O module is equipped with two dry contact digital inputs. The termi-
nals are DI11(17), DI12(18),DI21(19),DI22(20). The circuit is simplified as:
When the Switch is open, there is no current flow in the diode side of the optical coupler,
the triode is off, OUT is in low state. When the Switch is closed, there is current flow in the
diode side, the triode is on, OUT is in high state. In this way, the "high" and "low" state of
OUT correspondes to "closed" and "open" state of the switch.
I/O module has built in power supply, digital input does not require external power supply.
DI wire size is AWG22-16 or 0. 5-1. 5mm
2
.
Analog Output
AcuDC 240 I/O module offers two Analog Outputs. The output type is 0-20mA/4-20mA(max
24mA), 0-5V/1-5V(max 6V)(as Figure 2. 14 shows). Each module can only have one type of
Figure
2-13
Digital Input
OUT
DIn2
DIn1
K
AcuDC 240
24 +
24 G
Optical Coupler
Internal Power Supply