78M6610+PSU/EK#1 Maxim Integrated, 78M6610+PSU/EK#1 Datasheet - Page 23

• Manufacturer Part Number: 78M6610+PSU/EK#1
• Description: Development Boards & Kits - Other Processors 78M6610 EVAL KIT
• Manufacturer: Maxim Integrated

Specifications of 78M6610+PSU/EK#1

• Rohs: yes
• Part # Aliases: 90-X6610#KK1

scaled down from the AC inlet using a sensing element: resistor divider, voltage transformer, etc.
The current input is connected to current sensing element, generally a low value resistive shunt or current
transformer (CT).
The Iscale and Vscale parameters need to be set in order to match the full scale range of the current and
voltage inputs with the full scale range of the sensor.
Examples
Voltage: A voltage divider produces an output of 250 mV (peak) with 230 V (peak) applied at its input. A
resolution of 1 mV is needed. In this case, the value of VSCALE register should be:
in 1/1000 of Degree Celsius. For example, by setting the Tscale register to 1000, a temperature of 27°C
is reported as 27000 in the Temperature register.
3.2 Scaling Registers (Iscale, Vscale, Pscale, Tscale, Fscale)
The scaling registers can be used to set the full-scale values and choosing the resolution of related
parameters and results.
For voltage and current inputs, full scale is defined as +/-250 mV (DC or Peak). The voltage input is usually
VSCALE = 230 * 1000 = 230000
Current: A current shunt produces a voltage drop of 250 mV (peak) at 30 A (peak). A resolution of 1 mA is
needed. In this case the value of ISCALE register should be:
ISCALE = 30 * 1000 = 30000
Power: To set the power scaling register PSCALE it is necessary to multiply the full-scale voltage by the
full-scale current and by the desired resolution. For 1 mW resolution:
PSCALE: 230 volts x 30 amps x 1000 = 6900000 mw. The value of Pscale register should be set to 6900000.
The scaling registers for Line Frequency, Power Factor, and Temperature do not set full scale values.
They only set resolution. For example, setting Tscale to 1000 the value of the temperature is represented
Rev 1
Scaling Register
Note
All 78M6610+PSU registers are 24 bits and most are signed. The largest signed integer is
+/- 8388608. In case of larger numbers, a lower resolution must be chosen. For example,
10 mW versus 1 mW is case of PSCALE register.
PFscale
Vscale
Pscale
Tscale
Fscale
Iscale
Irms Ifund Iharm Ihi Ilo Ipeak Imax Itarget
Vrms Vfund Vharm Vhi Vlo Vpeak Vsurge Vsag Vdrop Vmin Vmax Vtarget
RelayOnMin RelayOnMax RelayOffMin RelayOffMax
Power VA VAR Paverage Pfund Pharm Qfund Qharm Pmax
PF
Temperature Tmin Tmax Xtemperature Xmin Xmax
Frequency Fmin Fmax
Table 4: Registers with Scalable Values
Registers Affected by Scaling
78M6610+PSU Data Sheet
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