Attachment Q - Elevator Disconnect.pdf

Elevator Control Switch

Industry Application IA00801001E

2 EATON CORPORATION Cutler-Hammer

Elevator Control Switch Industry Application IA00801001E April 2007

Why do Buildings Require Eaton Elevator Disconnects?

The Eaton Elevator Disconnect is a simple, all-in-one solution that takes the mystery out of meet-ing the many codes associated with fire protection and safety in elevator shafts. The model national building codes that prescribe the requirements for sprinklers, elevators and electri-cal equipment and how the vari-ous systems shall interact are:

NFPA

T

(National Electrical Code

NFPA 72

(National Fire Alarm Code

ANSI/ASME A17.1

(Safety Code for Elevators and Escalators)

NFPA 13 (Installation of Sprinkler Systems)

In addition to these national codes, state and local jurisdic-tions or other agencies of the government (such as the Veteran’s Administration) may edit or amend the codes, as they deem necessary for public safety.

This paper will illustrate how the Eaton Elevator Disconnect enables consultants, contractors and building owners to install a single device that meets the requirements of the various codes.

Why is There a Need for the Eaton Elevator Disconnect?

According to 2002 NFPA 13, 8.14.5, fire sprinkler protection is required (with some excep-tions) at the top and bottom of elevator shafts. Additionally, NFPA 13 requires the installation of sprinklers in the elevator machine room. When sprinkler heads are installed in elevator shafts, or in elevator machine rooms, then they must also be installed according to the State- Adopted Elevator Code (in many cases ANSI/ASME A17.1).

The ASME A17.1 Safety Code for Elevators and Escalators, Rule 102.2 (c) (3), requires the shutdown of power to the elevator prior to the application of water in the elevator machine room or hoistway.

Shutdown of power is usually accomplished with the use of a shunt trip device in the elevator circuit, and is done for two valid safety concerns.

The first of these is to minimize the potential for electric shock due to the release of water on energized electrical equipment.

The second, and less obvious, is to reduce the possibility of elevator car slippage after the car has gone to the recall floor and the doors have opened. Slip-page is possible when the hoist-ing equipment (cables, sheave, braking system, etc.) become wet from discharged water.

The Eaton Elevator Disconnect is a fusible switch that is equipped with a shunt trip mech-anism. The shunt trip is operated by a control relay (called a Fire Safety Interface Relay) in the unit that is wired to a normally open contact in the remote Fire Alarm Control Panel (FACP).

FIGURE 1. TYPICAL HYDRAULIC ELEVATOR COMPONENTS

AND REQUIREMENTS

1 NFPA 13 requires sprinklers in elevator shaft (with exceptions) and in control room.

2 ASME A17.1 (Safety Code for Elevators and Escalators) requires shutdown of power to the elevator prior to the release of water.

3 NFPA 72 (Fire Alarm Code) requires control circuit for elevator shutdown to be monitored for the loss of voltage.

4 NEC requires standby power systems such as a battery lowering device to be disconnected by an auxiliary contact in the elevator disconnect.

Sprinkler System

Fluid Tank Controller

Elevator Disconnect

Battery Lowering Device

Sprinklers

EATON CORPORATION Cutler-Hammer

Elevator Control Switch Industry Application IA00801001E

R

Copyright 2007

When the FACP receives a signal from the fire alarm system that there is going to be a sprinkler release in an elevator shaft, a normally open contact in the FACP closes, energizing the Fire Safety Interface Relay complet-ing a circuit to initiate a trip.

The Fire Safety Interface Relay is available with a 120-volt ac or 24-volt dc coil. The 120-volt coil should be selected when powered by the

Elevator Disconnect control circuit, and the 24-volt relay should be selected when the power is sup-plied from the fire alarm system.

In addition to turning off power, the model codes require other functions that are satisfied by the Eaton Elevator Discon-nect. One of these requirements is that the shunt trip control cir-cuit requires monitoring. The 2002 NFPA 72 (Fire Alarm Code) in Section 6.15.4.4 requires:

Control circuits to shut down ele-vator power shall be monitored for the presence of operating voltage. Loss of voltage to the control circuit for the disconnect-ing means shall cause a supervi-sory signal to be indicated at the control unit and required remote annunciation.

Thus, there is a requirement to monitor and annunciate the presence of shunt trip control power. This is accomplished in the Eaton Elevator Disconnect by the Fire Alarm Voltage Monitor-ing Relay option. This relay is either a SPDT or a 3PDT relay.

When control power is present, the closed relay contacts com-plete a circuit to the FACP that indicate the presence of control voltage. If control voltage is lost, the contact opens, signaling an alarm at the FACP and/or moni-toring and annunciating a single elevator, all that is required is the single-pole relay. When wiring multiple switches (for multiple elevators), the 3-pole relay option should be chosen. However, if there is a doubt, selecting the 3-pole relay will provide all the functionality that is needed.

Additional Requirements and Concerns

Many elevators are equipped with backup power supplies to allow the elevator to be lowered if power is lost. For example, many hydraulic elevators are equipped with a battery system which opens a solenoid to lower the elevator, and then provides power to open the elevator doors.

This battery-lowering device is viewed by the NEC as an “emergency or standby power system,” and is governed by Article 620.91.

Paragraph (C) requires that the main discon-nect be provided with an auxil-iary contact that disconnects the additional power source from the load when the disconnecting means is in the open position.

The purpose of this auxiliary contact is to disconnect the backup power system when the elevator switch is opened to prevent the elevator from automatically lowering while being maintained — which would endanger maintenance personnel.

The Eaton Elevator Disconnect is supplied with a standard set of 1NO and 1NC auxiliary contacts that are wired to the terminal blocks for this feature.

Other manufacturers offer this as an option.

FIGURE 2. SHUNT TRIP DEVICE WIRING DIAGRAM

Shunt Trip Device

From Feeder L1 L2 L3

Battery Lowering Device

To Elevator Controller

1. A shunt trip device is required if the hoistway and/or machine room is sprinklered.

2. The location of the shunt trip device is required to be in the elevator machine room.

To heat sensor(s) or flow control sensor.

■ Auxiliary Contact for Battery Lowering device required by Art. 620-91(C). Purpose of this contact is to distinguish between an actual power failure and the opening of the disconnect for maintenance.

■ Must be provided with overcurrent protection.

■ Must be lockable in the open position.

■ Must be externally operable.

Shunt trip control voltage must be monitored for loss of voltage. Loss of voltage is required to activate an annunciator on the control unit. The building fire alarm control unit may be utilized for this purpose (ref. NFPA 72 3-9.4).

© 2007 Eaton Corporation All Rights Reserved Printed in USA Publication No. IA00801001E/ Z5450 April 2007

An additional concern that is not code related is accidental signal-ing of a loss of voltage if a switch is turned off for maintenance or testing. For example, if an Eaton Elevator Disconnect is turned off to perform routine maintenance, the control voltage will be dis-connected and will send a signal to the FACP — which may alert the local fire department and initiate a fire call.

To solve this problem, an optional micro switch mounted on the main switch can be sup-plied and field-wired in parallel with the alarm contact on the Voltage Monitoring relay. Wiring in this fashion would prevent an alarm signal from being sent when the Eaton Elevator Disconnect is turned off for routine maintenance.

An additional standard feature on the Eaton Elevator Dis-connect is a Key-To-Test switch to perform a functional test of the operation of the shunt trip. A pilot light signaling that the switch is ON and a neutral lug are the only other available options.

The available enclosures include

NEMA

1, 3R, 12 and 4 (painted), allowing the Eaton Elevator Disconnect to be mounted in virtually any standard operating environment.

In summary, the Eaton Elevator Disconnect is an all-in-one solution for meeting the various codes associated with elevator shutdown and monitoring. It is clearly the best choice for engineers and con-tractors that need to provide code-compliant solutions — for whichever code needs to be met!

Elevator Control Switch Features

Standard

30 – 400 ampere, 600 Vac 3-phase fused power switch.

Note:

400 ampere available mid 2007.

200,000 ampere rms short circuit current rating.

Shunt trip 120 volts.

Control power terminal block.

Ground lug per NEC.

Class J fuse mounting only (Class J fuses not included).

Key-To-Test switch 120 volts.

Mechanically interlocked auxiliary contact for hydraulic elevators with automatic recall (5 A, 120 Vac rated) 1NO, 1NC.

National Electrical Code and NEC are registered trademarks of the National Fire Protection Asso-ciation, Quince, Mass. NFPA and the National Fire Alarm Code are registered trade marks of the National Fire Protection Association.

Optional

Control power transformer with fuses and blocks.

Fire safety interface relay.

Pilot light — ON.

Isolated neutral lug (oversized 200% rated neutral option available where required by excessive non-linear loads).

Fire Alarm Voltage Monitoring Relay (to monitor shunt trip voltage).

NEMA, 3R, 4 and 12 enclosures available through 400 amperes.

Note:

400 ampere available mid 2007.

Phase failure and undervoltage relay available, consult factory.

For added protection, use Eaton fuse covers to improve maintenance personnel protection, through 200 amperes (OSHA 1910.333, Paragraph C).

NEMA is the registered trademark and service mark of the National Electrical Manufacturers Association. UL is a registered trademark of Underwriters Laboratories Inc.

ELEVATOR CONTROL SWITCH CATALOG NUMBERING SYSTEM

100 VA with Primary and Secondary fusing (120 Volt Secondary).

Prefix

ES = Elevator Control Switch

Ampere Rating

1 = 30 A 2 = 60 A 3 = 100 A 4 = 200 A

Control Transformer 1

T2 = 208 Volt T3 = 240 Volt T1 = 480 Volt T4 = 600 Volt

Fire Safety Interface Relay

(3PDT, 10 A, 120 V)

R2 = 24 Vdc Coil R1 = 120 Vac Coil

Pilot Light ON

G = Green R = Red W = White

Fire Alarm Voltage Monitoring Relay

(To Monitor Shunt Trip Voltage)

F1 = Single-Pole F3 = Three-Pole

Enclosure Options (NEMA 1 Standard With No Suffix Designation Required)

3 = NEMA 3R

D = NEMA 12

P = NEMA 4 Painted Steel

ES 1 T2 R2 G F1 3 N B

Neutral Lug

N = Isolated Full Capacity

Auxiliary Contacts

1NO/1NC

B = Main Switch

Eaton Corporation Electrical Group 1000 Cherrington Parkway Moon Township, PA 15108 United States

877-ETN CARE (877-386-2273)

Eaton.com