AMETEK MX Series Rev: AY - Manual (Page 33)

User Manual – Rev AY AMETEK Programmable Power
MX Series 33
2.6.6 SNK (AC or DC) Option Specifications
The –SNK or current sink option enables the MX power source to sink current from the unit under
test. This mode of operation is particularly useful when testing grid-tied products that feed energy
back onto the grid. The ability of the MX to simulate the grid provides unique opportunities to test the
EUT for compatibility to commonly occurring line anomalies like voltage and/or frequency fluctuations.
Examples of these types of EUT are inverters (PV Solar, Wind) hybrid drive systems, regenerative
breaks.
The SNK option requires special amplifiers that have a different control loop from the standard MX
amplifiers. Consequently, the upper frequency limit of an MX configured with the –SNK option is
500Hz as opposed to the standard 819Hz. Also, the voltage distortion levels are slightly higher than
on MX units without this option.
-SNK Option: The following specifications apply to the AC mode unless specified otherwise
Frequency
Range: -HF option: 16 Hz - 500 Hz
Resolution: 0.01 Hz < from 16.00 to 81.92 Hz
0.1 Hz > from 82.0 to 500.0 Hz
Accuracy: ± 0.01 %
±0.25 % for –FC option
Phase
Accuracy: 16 - 100 Hz: < 1.5°
100 - 500 Hz: < 2°
Voltage
Distortion THD 1 :
(Resistive full load)
< 1 % @ 16 - 66 Hz
< 2 % @ 66 - 500 Hz
Power
Capability (AC & DC) Full power for the AC or DC mode can be returned into MX as long as
current does not exceed maximum current limit setting for selected range.
Refer to Figures 2-4 and 2-5 for the maximum DC current. See
REGENERATE CONTROL screen for protection settings in REGEN
mode.
Without –SNK option MX units without the SNK will generate an warning message (Error 31) if
more than 20% of available power (per phase) is regenerated by the load.
It will shut off (Error 32) if the negative power reaches 30% of available
power.
Programmable Output Impedance (available on MX15-1Pi, MX30-30Pi and MX45-3Pi only)
Auto-disabled Programmable impedance is turned off as soon as a regenerative load is
detected. Once turned off, it will remain off until programmed by user
again. This is required as programmable impedance is based on
delivering current which is not the case when driving a regenerative load.
Measurements
Power Regenerated power is displayed with a negative sign to indicate direction
of power flow.
All other specifications of the MX system remain unchanged if this option is installed.
1
The distortion specification for the MX Series is valid for pure (inductance < 12 uH) resistive load conditions and using a
30 KHz LP filter on distortion meter.