Banner MMD-TA-11B Muting Modules - Manual (Page 24)

22
P/N 116390 rev. C
Banner Engineering Corp. • Minneapolis, U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
MMD-TA-11B / MMD-TA-12B Muting Module
Instruction Manual
System Installation
3.5.6.2 Generic SSI and MSSI Hookups
To fully understand category requirements, refer to standard
ISO 13849-1 (EN954-1). The following is general in nature
and is intended to provide only basic guidance. Each guarding
application has its unique set of requirements; it is the user’s
responsibility to ensure that all local, state, and national laws,
rules, codes, and regulations are satisfied.
In addition to the use of well-tried, tested, and robust
components, and generally accepted principles (including fault
exclusion), the safety function depends on the use of safety-
rated devices. These devices are specially designed to reduce
the probability of failing to an unsafe condition, and typically are
third-party certified to a recognized safety standard.
Category 2
To meet the requirements of a category 2 application, any device
connected to the SSI and MSSI inputs must meet certain criteria.
For example, a “type 2” light screen (curtain) that meets IEC
61496-1/-2 is a device that meets category 2 requirements.
A category 2 safety function must be tested/checked at suitable
intervals, the frequency determined by the application’s risk
assessment. It should be noted that a single fault may cause the
loss of the safety function.
The principle of fault exclusion must be incorporated into the
design and installation to either eliminate, or reduce to an
acceptable (minimal) level of risk, the possibility of undetected
faults or failures that can result in the loss of the safety function.
Category 3
To meet the requirements of a category 3 application, any device
connected to the SSI and MSSI inputs must meet certain criteria.
For example, a “type 3” laser area scanner that meets IEC
61496-1/-3 is a device that meets category 3 requirements.
In a category 3 safety application, a single fault must not cause
the loss of the safety function. This is usually accomplished
by using redundant safety inputs or outputs from the safety-
rated device. Faults should be detected whenever reasonably
practicable, although a short circuit between input channels or
safety outputs may not be detected. It should be noted that an
accumulation of faults may cause the loss of the safety function.
The principle of fault exclusion must be incorporated into the
design and installation to either eliminate, or reduce to an
acceptable (minimal) level of risk, the possibility of undetected
faults or catastrophic failures that could result in the loss of the
safety function.
Figure 3-13a. MSSI and SSI Category 2 interfacing: positive-
opening switch
+24V dc 0V
(a)
MSSI or SSI
(b)
(c)
(d)
MMD-TA-..B A1
S12
S11
A2
S22
S21
X6
X5
X8
X7
Figure 3-14a. MSSI and SSI Category 3 interfacing: two
positive-opening switches per single guard
(a)
MSSI or SSI
(b)
(c)
(d)
A1
X6
X5
X7
X8
S12
S11
S21
S22
+24V dc 0V
MMD-TA-..B
A2
Figure 3-13b. MSSI and SSI Category 2 interfacing: Category 2
safeguarding device (e.g., EZ-SCREEN “Type 2”
or AOPD type 2 per IEC 61496-1/-2)
+24V dc
EZ-SCREEN
Type 2
0V
0V* +V
(a)
MSSI or SSI
(b)
(c)
(d)
MMD-TA-..B A1
S12
S11
A2
+
+
S22
S21
X6
X5
X8
X7
Figure 3-14b. MSSI and SSI Category 3 interfacing: category 3
safeguarding device with output fault monitoring
(e.g., type 3 area scanner AOPDDR per
IEC 61496-1/-3)
+24V dc
Safeguard with
Output Fault
Monitoring
0V
(a)
MSSI or SSI
(b)
(c)
(d)
MMD-TA-..B A1
S12
S11
A2
+
+
S22
S21
X6
X5
X8
X7