Extech Instruments 407907 User manual

,User's Manual
RTD Thermometer
Model 407907
Introduction
Congratulations on your purchase of the Heavy Duty Extech 407907 RTD Thermometer
which offers high precision and selectable 0.1oand 0.01oresolution. The LCD display
provides low battery and overload indication. Selectable temperature units °C & °F
provides measurement versatility. Careful use of this meter will provide years of reliable
service.

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Warranty
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts and
workmanship for one year from date of shipment (a six month limited warranty applies on sensors
and cables). If it should become necessary to return the instrument for service during or beyond the
warranty period, contact the Customer Service Department at [phone] ext. 210 for
authorization or visit our website at www.extech.com (click on Contact Extech and go to Service
Department to request an RA number). A Return Authorization (RA) number must be issued before
any product is returned to Extech. The sender is responsible for shipping charges, freight, insurance
and proper packaging to prevent damage in transit. This warranty does not apply to defects resulting
from action of the user such as misuse, improper wiring, operation outside of specification, improper
maintenance or repair, or unauthorized modification. Extech specifically disclaims any implied
warranties or merchantability or fitness for a specific purpose and will not be liable for any direct,
indirect, incidental or consequential damages. Extech's total liability is limited to repair or replacement
of the product. The warranty set forth above is inclusive and no other warranty, whether written or
oral, is expressed or implied.
Specifications
General Specifications
Display 4-1/2 digit (20,000 count) LCD display with over-range
and low battery indication
Measurement Temperature (selectable °C & °F units)
Data Hold Freezes displayed reading
RTD Sensor (optional) 4-wire platinum 100ΩRTD;
0.00385 alpha coefficient (meets DIN IEC 751)
RTD Sensor jack Proprietary 4 pin circular connector
(uses optional Extech RTD sensor)
Sampling Time Approximately 0.4 seconds
Memory record/recall Meter stores Maximum and Minimum readings
Data Output RS-232 PC Interface
Operating conditions Temperature: 32°F to 122°F (0°C to 50°C); RH: < 80%
Power Supply 9V battery
Power consumption 15 mA DC (approx.)
Weight 0.62 lbs. (285g)
Dimensions 7.1 x 2.8 x 1.3” (180 x 72 x 32 mm)
Range Specifications
Temperature Ranges Resolution Accuracy (% of reading)
-199.99oto 392.00o F0.01oF
oF
392.0oto 1562.0oF 0.1o F
± (0.1% + 0.4oF)
-199.99oto 199.00oC0.01oC
oC
200.0oto 850.0oC 0.1o C
± (0.1% + 0.2oC)
Accuracy specifications apply to the meter only. Probe accuracy is additional.

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Meter Description
1. RTD probe connector
2. RS232 connector
3. LCD display
4. Keypad
5. RTD probe
6. Battery compartment (rear)
7. Protective holster
Operation
Connecting the optional RTD probe
Plug the optional 4-wire RTD probe into the jack at the top of the meter. The jack is keyed
so that the probe cannot be incorrectly inserted; however use care when inserting to avoid
pin damage.
Powering the meter
To power the meter, slide the OFF/ON switch to the ON position. If the display remains
blank, check the 9V battery (rear compartment). Slide the switch to the OFF position to
turn the meter off. Remove the battery if the meter is to be stored for long periods.
Selecting units of measure
Press the oF/oC button to select the desired temperature units. The LCD display will show
the oCor the oFsymbol to indicate the currently selected unit of measure.
Selecting the resolution
The meter offers 0.1oand 0.01odisplay resolution. To select the resolution use the
0.01o/0.1oswitch. The display will reflect the currently selected resolution. Use the
specifications shown earlier in this manual to determine the best resolution for the
measurement range of a given application.
Taking measurements
Once the meter has been setup and a probe has been inserted in the jack at the top of the
meter, place the temperature probe in the area under test. Give the meter several seconds
to stabilize. Read the temperature measurement on the LCD. If dashes appear on the
display, either the reading is out of range or the RTD probe is not connected (or defective).
Maximum and Minimum (MAX/MIN) Record and Recall
When selected, the recording function stores the MAX/MIN readings for later recall.
1. Press the RECORD button once. The RECORD indicator will appear on the display.
2. After readings are taken, press the RECALL button to view the maximum reading. The
MAX indicator will appear on the display to inform the user that the reading now on the
display is the highest reading since the RECORD button was first pressed.
3. Press the RECALL button again to view the minimum reading. The MIN indicator will
appear on the display to inform the user that the reading now on the display is the
lowest since the RECORD button was first pressed.
4. To return to normal operation, press the RECORD button again. The RECORD, MAX,
and MIN indicators will extinguish.

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
Support Hotlines [phone]
Tech support: Ext. 200; Email: [email protected]
Repair/Returns: Ext. 210; Email: [e-mail]
Website: www.extech.com
Top View
Data Hold
To freeze a reading on the LCD, press the HOLD button. Temperature readings do take
several seconds to stabilize, therefore use Data Hold only after a reading has fully
stabilized. Press the HOLD button again to return the meter to normal operation.
RS-232 PC Interface
The meter includes a built-in RS232 serial data port. This interface was designed to
operate with the Extech Data Acquisition Software (Extech Part Number 407001) and
enables the user to store readings on a PC. For more information, contact Extech or refer
to the manual accompanying the software for details.
Battery Replacement
The low battery indicator (battery symbol) appears on the LCD when the 9V battery needs
replacing. Reliable readings can be obtained for several hours after the first appearance of
the low battery indicator. To replace the battery:
1. Remove the meter’s rubber protective holster.
2. Remove the battery compartment cover (back of meter) using a small coin or
screwdriver.
3. Replace the 9V battery (heavy duty, alkaline type) and reinstall the cover.
4. Replace the rubber holster.
4-wire RTD input jack pin-out
Calibration and Repair Services
Extech offers complete repair and calibration services for all of the products we sell.
For periodic calibration, NIST certification or repair of any Extech product, call customer
service for details on services available. Extech recommends that calibration be performed
on an annual basis to insure calibration integrity.
Copyright ©2001 Extech Instruments Corporation.
All rights reserved including the right of reproduction in whole or in part in any form.
100Ω