Megger DET24C Megger DET14C and DET24C Digital Ground Resistance Clamp Testers

DET14C and DET24C

Digital Earth Clamps

DET14C and DET24C

Digital Earth Clamps

■ Elliptical clamp shape improves access to

earth cables and straps up to 50 mm

■ Low maintenance flat jaw interface

■ Measures ground resistance from 0.05 Ω

to 1500 Ω

■ Measures true RMS ground leakage current

from 0.5 mA rms to 35 A rms

■ CAT IV 600 V safety rating

■ Backlit LCD Display

DESCRIPTION

The DET14C and DET24C represent a new generation of earth/
ground clamp-on resistance testers. These instruments induce a
test current into earth systems and measure ground resistance
in multi ground installations without needing to disconnect the
ground. They offer market leading access, advanced features, simple
operation and CAT IV 600 V safety protection.

Designed with flat core ends they prevent dirt build up, ensuring
measurement integrity and improved reliability over products with
interlocking teeth. Other enhancements over current generation
products include improved accuracy and up to 300% increase
in battery life. In electrically noisy environments the built-in filter
function offers increased noise immunity.

DET14C and DET24C also offer a true RMS AC current
measurement facility up to 35 Amps. The instrument’s ability to
measure current flowing in an earth cable is a useful safety feature,
especially if the earth cable has to be disconnected. A high current
flow to earth could draw an arc on dis-connection with potentially
severe consequences.

The elliptical shaped head design offers improved access to cables
and earth straps in space constrained locations. The clamp head
accommodates up to 37 mm diameter cable and 50 mm earth tapes
making them suitable for use in power stations, substations, towers
and many more facilities. Operation in dark and restricted areas is
facilitated by a display with backlight and an audible tone associated
with the hold key. Optimised jaw opening mechanism ensures proper
jaw closure without excessive use of force when opening the jaws.

The DET14C offers storage of results for later on-screen recall and
the DET24C supports a download of results via Bluetooth® into
PowerDB and PowerDB Lite, Megger’s acceptance and maintenance
test data management software. Stored data is indexed using a
sequential serial number together with a time and date stamp for
each record.

APPLICATION

The earth resistance clamp meters are particularly suitable for
measuring earth resistance in various installations such as buildings,
pylons and RF transmitter sites without system disconnection. In
addition, they can be used for the inspection and verification of
lightning protection systems and virtually any installation where a
current loop can be generated.

FEATURES AND BENEFITS

n Auto-current measurement safety feature

n Memory to record and view results

n Automatic self calibration

n Auto ranging

n High and low alarms

n Real time clock for date and time stamping of results

DET24C ADDITIONAL FEATURES

n Bluetooth® stored test results transfer to PC

n Advanced memory functionality with download

n Megger PowerDB/PowerDB Lite™ compatible

SPECIFICATIONS

Resistance measurements

Ground resistance Resolution Intrinsic range
certainty

0.05 Ω to 0.99 Ω 0.01 Ω ±1.5% ±0.05 Ω

1.00 Ω to 9.99 Ω 0.01 Ω ±1.5% ± 0.1Ω

10.0 Ω to 99.9 Ω 0.1 Ω ±2% ±0.5 Ω

100.0 Ω to 199.9 Ω 0.1 Ω ±5% ±1 Ω

200 Ω to 400 Ω 1 Ω ±10% ±10 Ω

400 Ω to 600 Ω 1 Ω ±10% ±10 Ω

600 Ω to 1200 Ω 10 Ω ±20%

1200 Ω to 1500 Ω 10 Ω ±35%

Frequency of measurement 1390 Hz.

The specification stated above is only maintained if the Jaws of
the DET14C and DET24C are kept clean at all times.

Alarm settings

Alarm type Range Resolution

Threshold 1 1 Ω to 1500 Ω 1 Ω

Threshold 2 1 Ω to 1500 Ω 1 Ω

Current range

(RMS)

Current range Resolution Intrinsic Certainty

0.5 mA to 0.99 mA 0.01 mA ±2% ±0.05 mA

1.00 mA to 9.99 mA 0.01 mA ±2% ±0.05 mA

10.0 mA to 99.9 mA 0.1 mA ±2% ±0.1 mA

100 mA to 999 mA 1 mA ±2% ±1 mA

1.00 A to 9.99 A 0.01 A ±2% ±0.01 A

10.0 A to 35.0 A 0.1 A ±2% ±0.1 A

True RMS readings up to a crest factor of 5.0 (peak current 40 A).
Accuracy guaranteed for 50 Hz and 60 Hz.

Measurement over the range 16 Hz to 400 Hz.

DET14C and DET24C

Digital Earth Clamps

Maximum jaw opening 39 mm

Maximum jaw inner 39 mm x 55 mm
dimensions

Display 4 + 6 digit with backlight

Battery type 4 x 1.5 V IEC LR6/AA alkaline

Battery life 24 hours continuous testing - see

Note 1
Note 1: Whilst measuring a 25 Ω
resistance without backlight

Auto power down 300 s (reset by jaw action or
button press)

Data logging DET14C 256 records DET24C
2 k records

Data download Bluetooth® interface
(DET24C only)

Range Selection: Automatic within each
mode

Sampling time <1 s

Hold function Yes with visual indicator

Alarm function Yes with visual indicator

Alarm/warning Buzzer: Yes

Operating temperature -20 °C to +50 °C, <85% RH
range and humidity

Storage temperature range -40 °C to +60 °C, <75% RH
and humidity

IP rating IP30 with jaws closed

Safety EN 61010-2-032

CATIV 600 V
Pollution degree 2

EMC Class B Compliant, IEC 61326,
BSEN 61326

Dimensions 248 mm (l) x 114 mm (b) x 49 mm (h)

Weight 985 g

The Bluetooth ® word mark and logos are registered trademarks
owned by Bluetooth SIG, Inc and is used under licence.

Maximum current is 100 A rms continuous and 200 A rms for 60 s
max at 50 Hz and 60 Hz

ORDERING INFORMATION

Description Order Code

DET14C Digital earth test clamp-on meter 1000-761

DET24C Digital earth test clamp-on meter 1007-331

SALES OFFICE

Megger Limited
Archcliffe Road Dover
CT17 9EN England
T [phone]

E [e-mail]

DET14C_DET24C_DS_en_V08

www.megger.com
ISO 9001

The word ‘Megger’ is a registered trademark

Description Order Code

Included accessories for DET14C and DET24C

Carrying case 1001-715

Carrying strap (wrist loop) 1001-716

User guide CD-ROM

Calibration check

Battery AA (Alkaline) (4 required)