Atec AEMC-DTR-8500 User Manual

Digital Transformer Ratiometer DTR®Model 8500 (pdf) 08/02

Technical Assistance [phone] www.aemc.com1of 5

The DTR®Model 8500 from AEMC

®

Instruments is a portable digital trans­former ratiometer designed for on-site
testing of power, potential and current
transformers. When connected to a
non-energized transformer, the DTR

®

Model 8500 accurately measures
primary to secondary turns ratio, while
simultaneously displaying polarity
and excitation current.

The DTR

®

is fully automatic and uses
an ANSI/IEEE compliant test method.
No user calibration, range selection,
hand cranking or tedious balancing
is required. At each measurement,
the DTR

®

automatically self-calibrates
and checks for open windings/
connections/ circuit breakers, short
circuits (excess excitation current),

incorrect test lead placement, and
reverse polarity. Measurements are
displayed quickly and accurately.

The DTR

®

Model 8500 is designed
with operator safety in mind. Tests
are performed at low voltage and,
unlike other ratiometers, step-down
excitation is employed. This method,
in conjunction with an integral H/X
reverse protection circuit, guards
against the generation of hazardous
test voltages normally associated
with transformer ratio measurement
instruments.

A large, dual line alpha-numeric LCD
display with adjustable contrast and
backlight guarantees day/night read­ability. Power is supplied by integral

NiCD battery (included) or by AC line.
Batteries are charged automatically
during AC operation.

Both rugged and reliable, the DTR

®

Model 8500 is built into an attractive,
sealed structural polypropylene case
designed to withstand the rigors of
utility and industrial field use.

Constructed using only the highest
quality electrical and mechanical
components, the DTR

®

Model 8500
sets the standard in advanced design,
engineering and workmanship, and it
will provide the user with years of
accurate and reliable measurements.

Digital Transformer Ratiometer
DTR

®

Model 8500

Digital Transformer Ratiometer DTR®Model 8500 (pdf) 08/02

Technical Assistance [phone] www.aemc.com2of 5

Features

• Designed for Power Transformers,
VTs, PTs and CTs

• Direct readings from 0.8000:1 to

1500.0:1

• Display Turns Ratio, Polarity and
Excitation Current simultaneously

• Dual power supply and operation:
integrated rechargeable NiCD
battery and AC supply

• Display warnings of incorrect lead
connections, reverse polarity, open
and short circuits

• Easy connection and test setup: no
calibration or balancing required

• Large dual line display with
adjustable contrast and backlight
ensures clear day/night visibility

• Low battery indicator

• Includes 15 ft leads

Applications

• Power transformers

• Potential transformers

•

Current transformers

In the shop or in the field — easy to connect and operate as shown on this
37 KVA transformer (left) and this 3 phase 2000 KVAtransformer.

CT Ratio Measurement