Watlow 145 User Manual

Series 145

User ’s Manual

Temperature Limit

1241 Bundy Boulevard, P.O. Box 5580, Winona, Minnesota USA 55987-5580

Phone: [phone], Fax: [phone], Internet: http://www.watlow.com

The Watlow Series 145 is a 1/16 DIN temperature limit
controller with a thermocouple or RTD sensor input. The
1/16 DIN case features a front panel that provides the
Series 145 with water and corrosion resistance.

The Series 145 is designed to meet the needs of a wide
range of safety applications. It is available with a wide
variety of thermocouple and RTD ranges.

The compact size of the limit allows more flexibility in
applications where space is a problem. The Series 145 has a
standard integral setpot and a front panel LED output
status indicator.

(1927)

Control Mode

• High or low limit, factory selectable

• Manual or automatic reset on power loss, factory selectable

• Latching alarm with manual reset on over or under temperature

Operator Interface

• Sealed membrane front panel

• Integral set point

• Dual temperature scale (°F and °C)

• LED indication of output status

• Dial scale calibrated to compensate for sensor
non-linearities

• Integral reset switch

Input

• Thermocouple or RTD available

• Thermocouple with automatic cold junction compensation

• Thermocouple may be isolated or grounded

• 2- or 3-wire RTD input, platinum 100Ω, 500Ω, or 1000Ω @ 0°C
calibrated for DIN 0.003850Ω/Ω °C curve

• Sensor break protection de-energizes output

Output

• Electromechanical relay, 3A, Form C, SPDT: 3A @ 240V~, 3A@
28VÎ (dc), resistive, 275VApilot duty rated

Accuracy

Adjustable Set Point

• Calibration accuracy: ±1% of span, at 77°F ±5°F (25°C ± 3°C)
ambient and rated line voltage ± 1%

• Set point accuracy: ±3% of dial scale

• Accuracy span: 1000°F (540°C) minimum

Fixed Set Point

• Calibration accuracy: ±10°F/±6°C of setting, at 77°F ±5°F (25°C
±3°C) ambient and rated line voltage ±1%

Temperature Stability

• Thermocouple: Typically 5µV/°F ambient (9µV/°C ambient) input
referenced

• RTD: Typically 0.2°F/°F ambient (0.2°C/°C ambient)

Voltage Stability

• ±0.01% of span (min span of 1000°F or 540°C) per % of rated line
voltage

Agency Approvals

• CE: EN61010 - Safety

EN61326 - Industrial Immunity, Class B Emissions
Installation Category 2, Pollution Degree 2

• 873, File #E43684

• to C22.2 No. 24, File #E43684

• Approved for use in commercial cooking applications

• FM Class 3545, File #J.I.3008516

Terminals

• Screw clamp terminal: 12-26 gauge wire

Power

• 120V~, +10%/-15%, 50/60 Hz

• 230V~ to 240~, +10%/-15%, 50/60 Hz

• 10VAmaximum power

Operating Environment

• 32 to 131°F (0 to 55°C)

• 0 to 90% RH, non-condensing

• Storage temperature: -4 to 185°F (-20 to 85°C)

Dimensions

• Height: 2.1 in (55 mm)

• Width: 2.1 in (55 mm)

• Depth: 4.0 in (102 mm)

• Behind panel: 3.50 in (89 mm)

• Front panel: 0.5 in (13 mm)

Weight

• 0.7 lb (0.3 kg)

UL®is a registered trademark of Underwriter’s Laboratories, Inc.
Note: Specifications subject to change without notice.

Specifications

General Description

$5.00 Made in the U.S.A.

Printed on Recycled Paper

10% Postconsumer Waste

0600-0004-0009 Rev C
August 2000

Supersedes: 0600-0004-0009 Rev B

TOT AL

3 Y ear Warranty

Registered Company

Winona, Minnesota USA

2 ■ Watlow Series 145 User’s Manual

Figure 2a — Series 145 dimensions.

Figure 2b — Series 145 panel cutout.

• Use the correct sensor type per the model number on the
unit sticker.

• Use the proper thermocouple or RTD polarity.

• Insulate the thermocouple mounting from the mounting
surface to prevent heat migration input errors.

• Thermocouple leads should be twisted pair wire and
routed separately from any other lines.

• In electrically noisy environments (heavy switching of
contactor, motors, solenoids, etc.) use shielded thermocou­ple lead wire with the shield connected at the sensor end
only.

• All wiring and fusing must conform to the National
Electric Code (NEC) NFPA70 and any other locally appli­cable codes.

• Fuse the independent load voltage on the L1 (hot) side
and connect it to the common (COM) side of the relay.

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CAUTION: A power disconnect switch located near the controller
is recommended to shut down power in case of controller
failure.

• Long lead lengths create electrical resistance. When using
a two-wire RTD, there will be an additional error for

every 1Ω of lead length resistance. That resistance when

added to the resistance of the RTD element, can result in
erroneous input to the temperature controller. To over­come this problem, use a three-wire RTD sensor, which
compensates for lead length resistance. When extension
wire is used for a three-wire RTD, all three extension
wires must have the same electrical resistance (i.e. same
gauge, copper stranded).

To Mount the Series 145

1. Make a panel cutout, using the dimensions in Figure 2b.

2. Check to see that the external case gasket of the Series
145 is facing the panel surface. Insure that the gasket is
not twisted and is seated within the case bezel flush with
the bezel. Insert the Series 145 into the cutout.

3. Slide the mounting collar over the back of the controller.
The two tabs of the mounting collar will fit into one of the
vent openings of the case.

4. While pressing the front of the case firmly against the
panel, tighten the two #8-32 screws until tight. Make sure
you cannot move the case within the cutout.

Figure 2c — Series 145 mounting.

NOTE: FM Approval requires limit switches to be suitably enclosed
to minimize casual readjustment of set temperature.

To Remove the Series 145

1. Remove the Series 145 by loosening the mounting screws
located on the mounting collar.

2. Using the screws, gently pry them away from the case.
This will lift the mounting tabs, allowing the collar to
slide backwards.

NOTE: To guarantee a proper seal, make sure the gasket between
the panel and the rim of the case is not twisted and is seated prop­erly. Press firmly.

NOTE: Make sure the rounded side of the D-shaped external case
gasket faces the panel surface and the gasket is fully seated.

Figure 2d — Series 145 interface.

User Interface

Installation

Wiring Guidelines

Dimensions

2.1 in

(55 mm)

square

4.0 in

(102 mm)

1.77 to 1.79 in
(45.0 to

2.10"

45.5 mm)

Panel Cutout

1.77 to 1.79 in
(45.0 to

1.75"

45.5 mm)

0.38 in
(9.7 mm)
Minimum

0.85 in

(20 mm)

Your Panel
Thickness

0.06 to 0.38 in

(1.5 to 9.7 mm)

Panel

External Gasket

Screw

Mounting Tab

Mounting Collar

Temperature Adjustment

150

350

300

Alarm

Indicator

150

50

100

Alarm

250

100

200

50

0

Type J T/C

˚C

200

RESET

˚F

400

450

250

500

550

300

315

600

Reset

Setpot

145