Dings Dynamics Group 70 Series Hazardous Location User Manual

70 Series Hazardous

Brake Instructions

DESCRIPTION

The 70 Series Brake is a direct acting, electro magnetically released, spring set unit that utilizes rotating and stationary
disc contact to supply positive braking action with quick release and setting capabilities at all times. Brakes which are
not provided with a floor mounting bracket are intended to be mounted as an integral part of electric motors listed for
corresponding hazardous locations where the acceptability of the combinations has been determined by Underwriter’s
Laboratories, Inc. The explosion-proof assembly is completed by assembly of the brakes to the motors.

READ THIS BULLETIN CAREFULLY BEFORE INSTALLING OR OPERATING THE
70 SERIES BRAKE. FAILURE TO COMPLY WITH THESE INSTRUCTIONS CANCELS
ALL WARRANTIES SINCE THE SAFETY OF THE UNIT MAY BE ENDANGERED BY
IMPROPER INSTALLATION OR OPERATING PROCEDURES.

Bulletin No. BK4606 (8/07)

4740 WEST ELECTRIC AVENUE MILWAUKEE, WI 53219  PHONE [phone]  FAX [phone]  www. dingsco.com

MOTOR MOUNTED* FOOT MOUNTED

MODEL MODEL

NO. Torque NO. Torque
R71010-9 10 lb. ft. FR71010-9 10 lb. ft.
R71015-9 15 lb. ft. FR71015-9 15 lb. ft.
R72025-9 25 lb. ft. FR72025-9 25 lb. ft.
R73035-9 35 lb. ft. FR73035-9 35 lb. ft.
R74050-9 50 lb. ft. FR74050-9 50 lb. ft.
R75075-9 75 lb. ft. FR75075-9 75 lb. ft.

*If a hazardous location brake is purchased by other than an
authorized electric motor manufacturer, a Foot Mounted brake
must be purchased to obtain the UL label.

CAUTION

DO NOT OPERATE MANUAL RELEASE
OR ENERGIZE BRAKE COIL BEFORE
INSTALLATION IN ORDER TO PRESERVE
PRE-ALIGNMENT OF ROTATING DISCS
FOR EASE OF INSTALLATION.

USE ONLY HUB FURNISHED BY DINGS
SPECIFICALLY FOR USE IN HAZARDOUS
LOCATION BRAKES. DO NOT OPERATE
BRAKES IN EXPLOSIVE ATMOSPHERE
WITH COVER OR COVER BOLTS
REMOVED.

MANUAL RELEASE (See Figure 1)

To manually release brake, push in release knob and rotate
counterclockwise until strikes stop-pin. Brake will remain
released until release knob is pushed in and turned clockwise
or until power is restored, automatically resetting the brake.

THERMAL RELEASE

If the brake overheats, the thermal release mechanism will release
spring pressure on the friction discs, releasing brake. To reset ther­mal release, allow brake to cool, then push in release knob (17)
and rotate clockwise until it strikes the stop-pin. Check brake
operation as overheating may indicate a broken lead wire or
burned out coil.

The thermal release mechanism has been calibrated at the factory
and the setting of the bimetal element and control rod MUST
NOT BE DISTURBED. If the mechanism does not function
properly, the complete pressure plate assembly (9), complete
magnet plate assembly (3), release gears (34) and items 31
through 50 must be returned to the factory for adjustments.

G060629-006

Figure 1.

Table 1. List of Models

WARNINGS

A. Read this bulletin carefully before installing or operating the brakes. Failure to comply

with the installation or operating instructions cancels all warranties and may cause
injury to personnel and damage to property.

B. DESCRIPTION

The 70 Series brake for hazardous location is a direct acting, electromagnetically
released, spring set brake that utilizes rotating and stationary disc contact to supply
positive braking action. Brakes can be mounted independently of any other equipment
by using a U.L. listed foot mounting bracket, or mounted to an electric motor listed for
hazardous locations. The brakes are equipped with a thermal overload mechanism that
prevents the external surfaces of the unit from exceeding the temperature rating for the
brake.

C. OPERATING INFORMATION

When the external surface of the brake approaches its temperature rating, the thermal
overload mechanism will automatically release the brake and hold it in the released
position. This prevents ignition of gases or suspended solis, assuming that brake’s
temperature rating is less than the air ignition temperature. The thermal overload
mechanism prevents the surface temperature of the brake from rising to a level that
could ignite the surrounding gases or dusts by releasing the brake and therefore,
stopping a further increase in temperature. Once the brake has been released by the
thermal overload mechanism, control over the rotation of the motor and the load is lost.
This uncontrolled rotation of the motor and movement of the load could cause injury to
personnel and damage to property.

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The thermal overload mechanism can be reset manually after a cooling off period. Before
resetting, the root cause for actuating the thermal overload mechanism needs to be determined
and corrected.

To minimize the possibility of overheating the brake to a point where the thermal overload
mechanism will be actuated, the performance of the brake has to be matched to the requirements
of the application.

When selecting the brake model, consideration has to be given to brake torque, thermal
capacity, electrical power supply, housing material and any unusual conditions.

BRAKE TORQUE
As a general rule, brake torque is matched to the full load motor torque (brake and motor shaft
at the same speed). Depending on the type of application, the torque sometimes is increased by
a safety factor of 1.5 to 2. If factors such as stopping time, travel distance during stopping and
others, are important, the exact torque requirement has to be calculated, using the methods
contained in Dings selection guide.

THERMAL CAPACITY
Thermal capacity describes the capacity of the brake to perform the maximum number of
stops without excessive heat buildup that will actuate the thermal overload mechanism or
damage internal brake parts. The maximum number of stops depends on the rating of the brake,
load to be stopped and speed from which stops are made. To calculate the thermal capacity
requirements of the application, use the methods contained in Dings selection guide.

ELECTRICAL POWER SUPPLY
The coil of the electromagnet, which supplies the releasing force under normal operating
conditions, will operate properly with a tolerance of plus or minus 10% of rated voltage. A volt­age higher than 110% will shorten the life of the coil considerably due to the higher temper­ature generated inside the coil. A voltage of less than 90% may prevent the armature from mov­ing towards the magnet frame. If this occurs, the coil will burn out within months.

UNUSUAL CONDITIONS

Please consult Dings Home Office, if ambient temperature is above 40oC (104oF), brake shaft
speed is over 3600 RPM, or any other unusual conditions exist.

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