expands the tour into its own window (only visible when embedded in another page.)LD400 and LD400P DC Electronic Loads: Technical Specifications
| INPUT SPECIFICATIONS | |
|---|---|
| Maximum Input Ratings | |
| Current | 80 Amps max. through the rear panel terminals. 30 Amps max. through the front panel terminals |
| Voltage | 80 Volts max. while conducting current. Surge suppressors start to conduct at 120V (nominal), Max. non-repetitive surge energy: 80 Joules |
| Power Continuous | 400 Watts max. up to 28°C, derating to 360 watts at 40°C |
| Power Short Term Note 1 | 600 Watts max. up to 28°C, for up to 60 seconds on-time, with off time at least double the on time. |
| Min. Operating Volts | <2V at 80A; typically equivalent to 25mOhm above 100mV (at 4A). |
| Off State Leakage | <10 mA (including voltage sense circuit input resistance) |
| Reverse Polarity | Diode will conduct; 80 Amps max. |
| Isolation Voltage | ± 300Vdc max, either load input to chassis ground |
| INPUT TERMINALS | |
|---|---|
| Rear Panel Input | Safety terminals accepting 5mm diameter wire, or 8mm spades up to 80 Amps max., or 4mm plugs at 30 Amps max. |
| Front Panel Input | Safety terminals accepting 4mm diameter wire, 4mm plugs or 6.5mm spades up to 30 Amps max. |
| EXTERNAL VOLTAGE SENSE | |
|---|---|
| Connection | Terminal block on rear panel. Sense selection by slide switch |
| Input Impedance | 680kOhm each input to load negative |
| Max. Sense Offset | 6V (allowance for backing-off supply for zero volt operation) |
| OPERATING MODES | |
|---|---|
| Constant Current Mode (CC) | |
| Current Ranges | 0 to 8 A (1 mA resolution) and 0 to 80 A (10 mA resolution) |
| Setting Accuracy | ± 0.2% ± 30 mA |
| Regulation | < 30 mA for 90% load power change (V > 2 Volts) |
| Temp. Coefficient | < (±0.02% ± 5 mA) per °C. |
| Slew Rate Ranges Note 2 | 8 A range: <2.5 Amp per s to >250 Amp per ms. |
| 80 A range | <25 Amp per s to >2500 Amp per ms. |
| Min. transition time Note 3 | 50 µs |
| Constant Power Mode (CP) | |
| Power Range | 0 to 400 (or 600) Watts |
| Setting Accuracy | ± 0.5% ± 2 W ± 30mA |
| Regulation | < 2% over 5 V to 75 V source voltage change (using remote sense) |
| Temp. Coefficient | <(± 0.1% ± 5mA) per °C |
| Slew Rate Ranges Note 2 | <40 W per s to >6000 W per ms |
| Min. transition time Note 3 | 150 µs |
| Constant Resistance Mode (CR) | |
| Resistance Ranges | 0.04 to 10 Ohm (0.01 Ohm resolution); 2 to 400 Ohm (0.1 Ohm resolution) |
| Setting Accuracy | ±0.5% ± 2 digits ± 30 mA |
| Regulation | < 2% for 90% load power change (V > 2 Volts, using remote sense) |
| Temp. Coefficient | < (±0.04% ± 5 mA ) per °C |
| Slew Rate Ranges Note 2 | 10Ohm range: <1Ohm per s to 100Ohm per ms |
| 400 Ohm range | <40 Ohm per s to 4000 Ohm per ms |
| Min. transition time Note 3 | 150 µs |
| Constant Conductance Mode (CG) | |
| Conductance Ranges | <0.01 to 1 A/V (1 mA/V resolution); <0.2 to 40 A/V (0.01 A/V resolution) |
| Setting Accuracy | ± 0.5% ± 2 digits ± 30 mA |
| Regulation | < 2% for 90% load power change (V > 2 Volts, using remote sense) |
| Temp. Coefficient | < (±0.04% ± 5 mA) per °C |
| Slew Rate Ranges Note 2 | 1 A/V range: <0.1 A/V per s to >10 A/V per ms |
| 40 A/V range | <4 A/V per s to >400 A/V per ms |
| Min. transition time Note 3 | 150 µs |
| Constant Voltage Mode (CV) | |
| Voltage Ranges | Vmin to 8 V (1 mV resolution) and Vmin to 80 V (10 mV resolution) |
| Vmin depends on current | typically <2V at 80A |
| Setting Accuracy | ± 0.2% ± 2 digits |
| Regulation | < 30 mV for 90% load power change (using remote sense) |
| Temp. Coefficient | < (0.02% + 1 mV) per °C |
| Slew Rate Ranges Note 2 | 8 V range: <0.8 V per s to >80 V per ms |
| 80 V range | 80 V range: <8 V per s to >800 V per ms |
| Min. transition time Note 3 | 150 µs |
| TRANSIENT CONTROL | |
|---|---|
| Transient Generator | |
| Pulse Repetition Rate | Adjustable from 0.01Hz (100 seconds) to 10kHz |
| Pulse Duty Cycle | 1% to 99% (percentage of period at Level A) |
| Setting Accuracy | ±1 % |
| Slew Rate Control | |
| The slew rate control applies to all changes of level whether caused by manual selection, remote control or the transient generator. The level change is a linear slew between the two level settings. The range available in each mode is shown above | |
| Setting Accuracy | ± 10% (on linear part of slope, excluding high frequency aberrations) |
| Variation in Level Settings | ± 5 digits of specified setting resolution for present mode and range |
| Oscillator Sync Output | |
| Connection | Terminal block on rear panel. Opto-isolated open collector output conducts during Level B phase of internal transient generator |
| Ratings | Max Off State Voltage: 30V. Collector Current: 2mA (typical) |
| DROPOUT VOLTAGE | |
|---|---|
| The load will cease to conduct if the applied voltage falls below the Dropout Voltage setting; active in all modes except Constant Voltage. The Dropout Voltage setting is also the threshold for the Slow Start facility and acts as an offset voltage in Constant Resistance mode | |
| Setting Accuracy | ± 2% ± 20mV |
| Slow Start | |
| If Slow Start is enabled, the load will not conduct any current until the source voltage reaches the Dropout Voltage setting; it will then ramp the controlled variable up (in CC, CP and CG modes) or down (in CR and CV modes) to the Level setting at a rate determined by the Slew Rate setting. | |
| METER SPECIFICATIONS | |
|---|---|
| Display Type | 256 x 112 pixel backlit graphic LCD |
| Measured Values | |
| Volts & Amps | Measured values of current through and voltage across the load |
| Watt & Ohms | Power and equivalent load resistance, calculated from Volts and Amps |
| Voltage Accuracy | ± 0.1% ± 2 digits |
| Current Accuracy | ± 0.2% ± 3 digits |
| CURRENT MONITOR OUTPUT | |
|---|---|
| Output Terminals | 4mm safety sockets on front panel or terminal block on rear panel |
| Output Impedance | 600W nominal, for >1MW load (e.g. oscilloscope) |
| Scaling | 50mV per Amp (4 Volts full scale) |
| Accuracy | ± 0.5% ± 5mV |
| Common Mode Range | ± 3V dc max. See note note 4 |
| ANALOGUE REMOTE CONTROL (LD400 and LD400P) | |
|---|---|
| External Control Input Characteristics | |
| Connection | Terminal block on rear panel |
| Input Impedance | 400kOhm each input to load negative |
| Common Mode Range | ± 100V to load negative |
| External Analogue Voltage Control | |
| Operating Mode | The applied voltage sets the operating level within the selected range |
| Scaling | 4 Volts full scale |
| Accuracy | ± 2% ± accuracy of selected range |
| Common Mode Rejection | Better than –66dB |
| External Logic Level (TTL) Control | |
| Operating Mode | The applied signal selects between Level A and Level B settings |
| Threshold | + 1.5V nominal. A logic high selects Level B |
| Remote Disable Input | |
| Connection | Terminal block on rear panel. Input to the LED of an opto-isolator through 1kW resistor |
| Threshold | Apply >+3V to disable load input (+12V maximum) |
| DIGITAL REMOTE CONTROL (LD400P only) | |
|---|---|
| The LD400P model provides LAN, USB, GPIB and RS232 interfaces for full remote control | |
| LAN | Ethernet 100/10base-T connection with auto cross-over detection. LXI v1.4 Core 2011 compliant |
| USB | Standard USB 2.0 connection. Operates as virtual COM port |
| GPIB | Option on LD400P. Conforming to IEEE488.1 and IEEE488.2. Capabilities: SH1, AH1, T6, L4, SR1, RL2, PP1, DC1, DT0, C0, E2 |
| RS232 | Standard 9-pin D connection. Baud rate: 9600 |
| PROTECTION | |
|---|---|
| Excess Power | The unit will attempt to limit the power to approx. 430 Watts; if this fails the unit will trip into the fault state at about 460 Watts. If intermittent mode operation is enabled, these levels are 610W and 630W |
| Protection Current | The input is disabled if the measured current exceeds a user set limit |
| Excess Current | The unit will trip into the fault state at nominally 92 Amps |
| Protection Voltage | The input is disabled if the measured voltage exceeds a user set limit |
| Excess Voltage | The unit will conduct a current pulse (to absorb inductively generated spikes) for 1ms at about 90V. The unit will trip into the fault state at nominally 106V. Surge suppressors will start to conduct above 120V |
| Temperature | The unit will trip into the fault state if the heatsink temperature exceeds safe levels |
| Sense Error | The unit will trip into the fault state if the external voltage sense is more than 6V below the internal sense |
| GENERAL | |
|---|---|
| AC Input | 110V–120V or 220V–240V AC ±10%, 50/60Hz. Installation Category II |
| Power Consumption | 30VA max. Mains lead rating 6A |
| Operating Range | + 5°C to + 40°C, 20% to 80% RH |
| Storage Range | -40°C to + 70°C |
| Environmental | Indoor use at altitudes up to 2000m, Pollution Degree 2 |
| Cooling | Variable speed fan. Air exit at rear. |
| Safety | Complies with EN61010-1 and EN61010-2-030 |
| EMC | Complies with EN61326 |
| Size | 130mm H (3U) x 212mm W (½ rack) x 435mm D |
| Weight | 5.7 kg |
| OPTIONS | |
|---|---|
| Option | RM460 4U 19-inch rack mount kit |
Specification Notes
- Note 1 In 600 Watt short-term operation mode the dynamic response is not specified, and both the slew rate and the transient oscillator frequency range are restricted. The slew rate limitation applies also to external voltage control. This mode is primarily intended for limited duration operation at a fixed level setting.
- Note 2 Slew Rate Ranges refer to the theoretical slope of the transition between two levels, regardless of whether that transition can be achieved when taking into account the level difference, the set transition duration, the minimum transition time, and the characteristics of the source.
- Note 3 Minimum Transition Time specification is an indication of the fastest available transition using a benign battery source and low inductance connections, with a minimum terminal voltage of 5V and a minimum current of 1A. The actual performance attainable with electronically regulated power supplies depends on the combination of source and load loop bandwidths and interconnection inductance.
- Note 4 The common mode capability of the current monitor is to provide tolerance of voltage drops in the cables. The monitor negative must be connected at some point to the load negative circuit.
Accuracy specifications apply for 18°C – 28°C, at 50W load power (in normal 400W mode), after 30 minutes operation at the set conditions; regulation specifies variation at other powers. Setting accuracies apply with slew rate at the ‘Default’ setting.