IET LABS, INC. in the GenRad Tradition

www.ietlabs.com

TEL: (516) 334-5959 • (800) 899-8438 • FAX: (516) 334-5988

High Accuracy

Micro-Ohmmeter

LOM-510A

Page 1 of 2

LOM Catalog Pages Dec. 2019

Features and accessories to assure

that very low resistance measure-

ments are accomplished accurately,

easily, and economically.

The LOM-510A has 4½ digits, 0.02% basic

accuracy and 1 μΩ resolution. Its 4-terminal

measurement technique eliminates lead

resistance errors and 80 dB of ac noise rejection

provides rock-steady readings even in noisy

locations. The unit comes with rugged 4-terminal

test clips and a large selection of optional probes,

clips and fixtures allowing attachment to any low-

resistance unknown.

Switched dc Mode:

Allows measurement of switch contacts,

welds, shunts, PC board tracks and other

primarily resistive elements. Thermal emf

effects are eliminated.

Constant dc Mode:

Suitable for measuring the resistance of

inductive components such as coils or

transformers.

Pulsed Mode:

Provides low drive current to allow

measurements of fuses, thermistors, and

other thermally sensitive devices.

Dry Circuit:

Assures that oxides and film contacts are

not punctured. The Dry Circuit Mode limits

the open circuit voltage to 50 mV. The

Model LOM-510A/20

limits the open circuit

voltage to 20 mV.

Model LOM-510A Micro-ohmmeter shown with

LOM-501C Standard 4-Terminal Kelvin clips

SW (Switched dc) Mode:

Current switched on for 166 ms, then off for

500 ms (25% duty cycle).

Pulsed Mode:

One cycle of SW (Switched dc) mode;

enabled by shorting two contacts on rear

panel connector.

Display:

4½ digit, 0.5 inch, red LED display.

Display Overrange Indication:

Flashes for DC (Continuous dc) and SW

(Switched dc)

blanks in Pulsed mode

Measurement Rate:

1.5 readings/second

Connections to Unknown:

4-terminal Kelvin leads with shield

SPECIFICATIONS

Accuracy:

SW (switched dc):

±(

0.02% + 2 counts +2 μΩ)

dc (continuous dc):

Typically ±(

0.04% + 2 counts + 2 μΩ)

Pulsed mode: ± (

0.02% + 4 counts + 2 μΩ)

Zero Adjust:

Active only in DC (Continuous dc) mode.

Noise Rejection:

80 dB for SW (Switched dc) and Pulsed Mode

60 dB for DC (Continuous dc) mode.

Range

(Full Scale)

Drive

Max Dissipation

Resolution

DC

SW

19.999 m

Ω

1 A

20 mW

5.0 mW

1 µ

Ω

199.99 m

Ω

.1 A

2.0 mW

.50 mW

10 µ

Ω

1.9999

Ω

10 mA

.2 mW

.05 mW

100 µ

Ω

19.999

Ω

1 mA

.02 mW

5 µW

1 m

Ω

199.99

Ω

.1 mA

.002 mW

0.5 µW

10 m

Ω

LOM-530 (CALIBRATION KIT FOR LOM-510A)

Stability

Max

Power

TempCo

Power

Coefficient

0.01

Ω

50 ppm/year

2 W

20 ppm/°C

0.1 ppm/mW

0.1

Ω

50 ppm/year

1 W

20 ppm/°C

0.1 ppm/mW

1

Ω

20 ppm/year

0.25 W

10 ppm/°C

0.5 ppm/mW

15

Ω

10 ppm/year

0.1 W

3 ppm/°C

0.5 ppm/mW

150

Ω

10 ppm/year

0.1 W

1 ppm/°C

0.5 ppm/mW

Temperature Range: 15° to 30°C

Storage Range: 0°C to 40°C

A convenient single unit containing a complete set of (5)

working standard grade resistors for complete calibration of

the micro-ohmmeter.

Ne

w

Features:

• 1 μΩ resolu on

• ± 0.02% basic accuracy

• Digital output

• Four measurement modes

• Auto-zero switched dc mode

• Probes for chips and traces

• New switch design, improves reliability

• New external voltage selector switch

• New IEC inlet adapter with fuse

Outputs:

5 BCD digits for value and polarity; Pulsed

Mode Control lines; power supply lines; 25

pin "D" connector.

Warm up time:

1 minute to rated accuracy

Accuracy vs. Temperature:

Stated accuracy applies over an ambient

temperature range of 18 to 27 °C. Error

doubles over the range of 10 to 40 °C.

Accessories Supplied:

LOM-501

test clips

Power Requirements:

105-125 Vac or 210-250 Vac; 50-60 Hz

selectable on rear panel

30 W max.

Mechanical:

Dimensions:

22.9 cm W x 5.1 cm H x 27.9 cm D

(9" x 2" x 11")

Weight:

2.7 kg (6 lb)