Datasheet

LD400 & LD400P - Technical Specifications (continued)
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.
REMOTE CONTROL (All Models)
External Control Input Characteristics
Connection: Terminal block on rear panel.
Input Impedance: 400kW 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 +3 to +5 V to disable load input.
REMOTE CONTROL (LD400P only)
Digital Remote Interfaces
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: 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: + 5ºC to + 40ºC, 20% to 80% RH.
Storage Range: – 40ºC to + 70ºC.
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.
Option: 19-inch rack mount kit.
Specification Notes
(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.
(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.
(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.
Accuracy specifications apply for 18°C – 28ºC, 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.
Thurlby Thandar Instruments Ltd. operates a policy of continuous development and reserves the right to
alter specifications without prior notice.
Designed and built in Europe by:
Thurlby Thandar Instruments Ltd.
Glebe Road, Huntingdon, Cambridgeshire. PE29 7DR United Kingdom
Tel: [phone] Fax: [phone]
Email: [e-mail] Web: www.tti-test.com
LD400 Brochure Iss. 1-D6