Atec 63800 User Manual

PROGRAMMABLE AC/DC ELECTRONIC LOAD MODEL 63800 SERIES

Chroma's 63800 Series AC/DC Electronic Loads are designed for testing uninterruptible power supplies(UPS), Off-Grid Inverters, AC sources and other power devices such as switches, circuit breakers, fuses and connectors.

The Chroma 63800 Loads can simulate load conditions under high crest factor and varying power factors with real time compensation even when the voltage waveform is distorted. This special feature provides real world simulation capability and prevents overstressing thereby giving reliable and unbiased test results.

The 63800's state of the art designed uses DSP technology to simulate non-linear rectified loads in a unique RLC operation mode. This mode improves stability by detecting the impedance of the UUT and dynamically

adjusting the load's control bandwidth to ensure system stability.

Comprehensive measurements allow users to monitor the output performance of UUT. Additionally, voltage & current signals can be routed to an oscilloscope through analog outputs. The instrument's GPIB/RS232 interface options provide remote control & monitor for system integration. In addition, built-in digital outputs may be used to control external relays for short circuit (crowbar) testing.

Chroma's 63800 Loads also feature fan speed control ensuring low acoustic noise. The diagnosis/protection functions include selfdiagnosis routines and protection against overpower, over-current, over-voltage and overtemperature.

Programmable AC/DC Electronic load

MODEL 63800 SERIES

Key Features :

■Power Rating : 1800W, 3600W, 4500W

■Voltage Range : 50V - 350Vrms

■Current Range : Up to 18Arms, 45Arms

■Peak Current : Up to 54A, 135A

■Parallel / 3-Phase Function

■Frequency Range : 45 to 440Hz, DC

■Crest Factor Range : 1.414 to 5.0

■Power Factor Range : 0 to 1 lead or lag (Rectified mode)

■CC, CR, CV, CP for DC Loading

■Constant & Rectified Load Modes for AC Loading

■Analog Voltage & Current Monitor

■Timing Measurement for Battery, UPS, Fuse and Breaker tests

■Measurement : V, I, PF, CF, P, Q, S, F, R, Ip-/+ and THDv

■Short circuit simulation

■Full Protection : OP, OC, OV and OT protection

■GPIB & RS-232 interfaces

Complete AC & DC Load Simulations

Chroma's 63800 AC/DC Electronic Load is designed for both AC & DC Load Simulations. Illustrated below are the various load modes which are available:

Model 63800

AC Load Simulation

DC Load Simulation

CC Mode

Constant Load Modes

Rectified Load Modes

CR Mode

CC Mode

RLC Mode

CV Mode

CR Mode

CP Mode

CP Mode

CP Mode

Inrush Mode

Rectified Mode

AC Load Simulation

The Model 63800 AC/DC Electronic Load provides two unique operating modes for AC load simulation; (1) Constant Load Modes and

(2) Rectified AC Load Modes. Each are described below.

Constant Load Modes

The Constant Load Modes allow users to set the following operating modes : CC, CR and CP mode. The CC & CP modes in this category allow users to program PF or CF, or both. For CR mode the PF is always set to 1.

When both the PF & CF of the loading current are programmed, the 63800 load controls power factor from 1 to 0 by shifting the current (with CF defined) relative to the input voltage to get desired displacement power factor. The power factor range will be limited based on crest factor programmed. If the programmed PF is positive then the current will lead the voltage waveform, in opposite, when PF is set negative, the current will then leg the voltage waveform. (See below)

PF

CFI

Figure 1: Crest Factor vs. Power Factor control Range

CFI = I peak / I rms

PF = True power / Apparent power

As seen in Figure 1, for a crest factor of 1.414, the programmed power factor can only be 1 if the input voltage is sine-wave. However, for a CF of 2.0, the acceptable PF ranges from 0.608 to 0.85; for CF = 3, the PF can then be set from 0.211 to 0.6, etc. So, higher crest factors enable wider range of power factors.