ES-FL-2A BANNER ENGINEERING, ES-FL-2A Datasheet - Page 3

• Manufacturer Part Number: ES-FL-2A
• Description: 20H6269
• Manufacturer: BANNER ENGINEERING

Specifications of ES-FL-2A

• Coil Voltage Vac Nom: 24V
• Coil Voltage Vdc Nom: 24V
• Contact Current Max: 4A
• Contact Voltage Ac Nom: 250V
• Contact Voltage Dc Nom: 250V
• Contact Configuration: DPDT-NC
• No. Of Poles: 2

The purpose of safety relay model ES-FL-2A is to increase the control reliability of an emergency stop circuit. The ANSI B11.19
standard states:
As indicated in Figure 2 or 3, a typical emergency stop switch offers two redundant switching contacts. In a properly-designed
machine stop circuit, the opening of either of the two emergency stop contacts immediately removes electrical power from the
machine control elements which react to stop hazardous machine motion and/or any other machine hazard. This redundancy of
stopping control offered by a two-pole emergency stop switch is the first step towards control reliability. However, failure or defeat
of one of the switch contacts to a short-circuit will go undetected, thereby removing the redundancy, and leaving the emergency
stop circuit prone to eventual failure.
The ES-FL-2A safety relay connects between the emergency stop switch and the machine emergency stop control elements. The
emergency stop switch becomes an input to the safety relay. The safety relay monitors the condition of both contacts of the
emergency stop switch. The output of the safety relay consists of two redundant output switching channels, each of which is the
series connection of two safety relay contacts (K1 and K2 in Figure 2). The Control Reliability section of ANSI B11.19 goes on to
state:
Safety relays K1 and K2 in the output circuit of the ES-FL-2A safety relay have mechanically-linked contacts which allow the safety
relay circuitry to monitor the contacts of K1 and K2 for failure. If the safety relay detects failure of any contact of either the input
emergency stop switch or the output relays, the safety relay output is disabled and cannot be reset.
The ES-FL-2A safety relay also provides a necessary reset function. ANSI B11 and NFPA 79 standards require that a reset routine
be performed after returning the emergency stop switch to its closed-contact position. This prevents the controlled machinery from
restarting by simply closing the emergency stop switch.
The two switching output circuits of the safety relay are rated for up to
250V ac at up to 4 amps (resistive load). A low-capacity non-safety
auxiliary contact (between terminals #41 and 42) provides a monitoring
signal for a process controller.
The ES-FL-2A emergency stop monitoring safety relay complies with
the following design standards:
UL991
EN418
EN954-1 Safety of Machines: Safety-related Parts of Controllers
The safety relay has indicators for input power and output relay contact
status (see Figure 1). There are no adjustments and no user-serviceable
parts. See page 7 for information regarding repair service.
SECTION 1 – Product Description
Tests for Safety Related Control Employing Solid-state
Devices
Emergency Stop Equipment - Functional Aspects, Principals
for Design
Part 1: General Design Directives (Safety Category 4)
“Control reliability of electrical, electronic, or pneumatic systems frequently consists of multiple,
“Electromechanical systems that require redundancy and checking of relay contacts should use
independent parallel or series circuitry or components so arranged that any single failure would
not significantly affect the stopping performance of the system or the machine tool. If a failure
of a component has occurred, this arrangement either sends a stop command to the machine
tool or prevents a successive cycle from being initiated.”
relays that are designed with mechanical linkages to provide relation between normally open and
normally closed contacts to check the contact operation.”
Figure 1. ES-FL-2A Status Indicators
Status Indicators
K2 Energized
K1 Energized
Power on
Input
E-Stop Safety Relay
ac/dc
24V
A2 S14 S24 S34 42 14
A1 S13 S23 S33 41 13
In A
In B
RESET
Machine Safety
ES-FL-2A
K3
K1
K2
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