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VisualDetect LCD

Chapter: Overview · Descrption · Options · Technical data · Item numbers

Upgraded voltage detection

VisualDetect LCD is an easily operated voltage detector and interface-tester. Its automatic, thorough self-test ensures reliable function. The permanently enabled interface-tester warns against defect interfaces. Additionally the LC-display indicates the measured current [I/µA] and frequency [f/Hz]. Thanks to the integrated configuration menu it can be adjusted to switchgears operated below nominal voltage on-site.

Article: VDL-01AB Display scheme VDS

Application and technique

VisualDetect LCD is a VDS (Voltage Detecting System) for the LR-System in compliance with IEC/EN 61243-5 (DIN VDE 0682 T415). Additionally the device connects to HR, MR and LRM string parts with the appropriate adapter.

The permanent indication of the evaluated interface current is realized by means of two bright LEDs, which display the conditions voltage absent, residual voltage, voltage present and string part ok respectively:

Condition Current (Uo = Un) Display
Voltage absent < 0,30 µA Green continuous light
Residual voltage 0,30 - 2,49 µA Green flashing light
Voltage present 2,50 - 3,19 µA Red flashing light
String part ok 3,20 - 15,0 µA Red continuous light
High current > 15,0 µA Red flashing light (90% On)

The determination is accomplished with an rms-value measuring method independent of the applied waveform, so that stepper motors, switching power supplies or wind turbines run with frequency inverters pose no threat. If operating / nominal voltage differ (the ratio is set), the threshold values will be readjusted accordingly.

The build-in ampere and frequency meter assists in compliant maintenance-testing of switchgears, as stated in section 5.26 of IEC/EN 61243-5, by providing explicit information via the dot matrix display:

Display Meaning
20,15uA / I>> Current, here 20,15 µA and
high current (equivalent to > 120% Un)
3,25 uA / Ok! Current, here 3,25 µA and
string part ok
2,50 uA / Def Current, here 2,50 µA and
string part defect
50.0 Hz / Signal ok Frequency 50,0 Hz and
clear signal
101.3 Hz / Faulty signal Frequency 101,3 Hz and
Frequency too high, faulty signal

The integrated self-test ensures unfailing operation. It starts automatically whenever the device is switched on. You merely plug the connection lead, with or without adapter, into the test jack of the device, push the power button once and the device checks the connection lead, the LEDs, the battery voltage and the correct functioning of electronic measuring circuits and software. If an error is detected you will be notified of fault condition by plain text, before it shuts down.

Basic equipment

Adapter inspection

A HR-, LRM- or LRP-adapter can be integrated into the self-test with the onboard adapter inspection. Though the chance of an adapter-failure is very narrow, you obtain a completely scrutinized voltage detector. If an LRP-adapter is detected the device automatically switches to the 1,0 µA LRP threshold value.

MR-adapter, LRM-adapter with fixed plug clearance and LRP-adapter with 6 mm electrodes are not testable for mechanical reasons.

Replaceable batteries

In order to keep time off due to battery exhaust minimal, the device is equipped with exchangeable lithium cells (2 pcs. CR123A).


Firmware modification

On request we can preset your custom operating / nominal voltage ratios for easy handling or personalize the menu navigation - as far as possible - according to your wishes.

Technical data

VisualDetect basic (VDL-01AB)
Connecting system LR
Impedance 2 MΩ at f=50 Hz
Threshold values
for Uo = Un
0,3 µA - residual voltage
2,4 µA - voltage present
3,2 µA - string part ok
15 µA  - high current
Frequency range < 10 ... > 200 Hz
Input voltage 0 - 65 V~
Plug proportions 1/4" Phone plug; 0,5 m connection lead.
Electronics 8 Bit MCU; 2 MHz clock; 10 Bit A/D
Display 1x LED green, 1x LED red,
2x 8 char LCD, backlight: yellow/green
Measurement range Current: 0,00 - 22,50 µA
Frequency: 10 - 450 Hz
Power supply 2 lithium cells, 6V
Dimension 150 x 80 x 35 mm
Weight approx. 270 g
Protection class IP 54

Subject to change without prior notice!


Order-No. Name
VDL-01AB VisualDetect LCD with adapter inspection
and exchangeable batteries
VDL-01AB/K ... with HR-LR Adapter in plastic case
VDL-01AB/L ... with HR-LR Adapter in leather wallet
MA-HL02 Test adapter HR to LR-system
MA-ML01 Test adapter MR to LR-system
adapter inspection not possible!
MA-LML01D Test adapter LRM to LR-system (Type D, flex)
MA-LML01F Test adapter LRM to LR-system (14 mm fixed)
adapter inspection not possible!
MA-LPL02D Test adapter LRP to LR-system (Type D, 4 mm)
MA-LPL02D/6 Test adapter LRP to LR-system (Type D, 6 mm)
adapter inspection not possible!
MA-LPL01D/CC Test adapter LRP to LR-system for CapaConnect
AB-KK01 Plastic case for VisualDetect LCD
AB-LT01 Leather wallet for VisualDetect LCD