As the “Repeater” mode is activated, the module forwards a signal (obtained by means of linear conversion of the digitized signal from the digital module, node of which corresponds to that selected in ZET7190-R module) to analog outputs. Source digital signal in the range «max input X value» – «min input X value» is transformed into output signal in the range (0-5) V.
In the repeater mode ZET7190-R can be used off-line without connection to PC. In the case if the CAN network has a device with a set node number, ZET7190-R will use it and will form an output signal based on the data received.
In the “Repeater” mode the module can be used as a transmitter for “4-20 mA” interface. Input voltage range (0-5) V forms limitation for current loop operation mode 4-20 mA – current loop impedance max value is limited by 240 Ohm.
For changing module settings in the current output module one should:
1) calculate output voltage range
Ur_min = R*0,004,
Ur_max = R*0,02,
where R – is the current loop impedance.
2) calculate ratios depending on the input values range
k = ∆Ur/∆Uin,
where ∆Ur = Ur_max-Ur_min, ∆Uin – repeated values range
b = Ur_min-k* Uin_min
3) calculate ratios to be recorded in the sensor settings
min input value = -b/k
max imput value = (5-b)/k
Example. Settings of ZET7190-R module in signal repeater mode from ZET7112 for connection via current loop interface 4…20 mA to ZET7180-I.
R = 120 Ohm
Ur_min = 120*0,004 = 0,48
Ur_max = 120*0,02 = 2,4
∆Ur = 1,96, ∆Ur-in = 16 (mPa)
k = 0,12; b = 0,48
Min input value = -4
Max input value = 37,6667