mpec SA380-IT, Руководство пользователя

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The preferred termination method is to situate the in-line resistor at the "monitored circuit end" of the termination to protect against cable
insulation fault, however this is at the discretion of the user.
If resistive cables are not fitted, incorrect readings will be obtained.
3.6.2 Via HI Z Outputs
It is common to perform monitored circuit functions on the same circuit that is used to power the SA380-IT device.
To simplify wiring it is possible to "jumper" across the power supply into "Channel 1" of the monitored circuits. This is achieved by the "HI Z"
outputs.
The "HI Z" outputs present the power supply voltage as an output, albeit with a 47 k resistor in each circuit leg. E.g.
BX HI Z is BX Supply with 47 k in series.
NX HI Z is NX Supply with 47 k in series.
This means that resistive cables are not required to jumper the HI Z outputs across to channel 1 as shown in the diagram below.
Network Rail users must use "Grey 0.75 mm A1" cable (supplied with the device) for these terminations.
Tools / Parts Required:
Ferrules
Crimp Tool
Resistive Cables (MPEC Part No. SA380-IT-RC)
Actions when using Resistive Cable:
Each monitored circuit can be AC or DC and range from 5 V to 160 V RMS.
Where possible, disconnect the voltage at the positive and negative termination point on the monitored circuits bus-bar.
Connect the end of the cable with the resistor fitted to the positive or "B leg" of the monitored circuit.
Connect the far end of the cable to the appropriate "B leg" connection at the rear of the SA380-IT.
Connect the end of the cable with the resistor fitted to the negative or "N leg" of the monitored circuit.
Connect the far end of the cable to the appropriate "N leg" connection at the rear of the SA380-IT.
The cables should be shortened at the SA380-IT end if possible.
Actions when using HiZ Outputs:
Connect "BX HI Z" to "B1" with standard cable (Do not use resistive cable).
Connect "NX HI Z" to "N1" with standard cable (Do not use resistive cable).
Never connect the SA380-IT directly to monitored circuits without: