Siemens 505-2557 installation and operation guide Input Flag Bits, Peak/Valley Hold Input Words

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Internal Register Structures (continued)

Input registers WX49 ± WX54 consist of special flag bits that may be interrogated in the controller ladder program to detect alarm conditions, overrange or underrange conditions, or arithmetic overflow conditions due to scaling operations. See Figure 3-3.

WX49	Channel 1±16 Alarm flag bits
WX50	Channel 1±16 High alarm flag bits
WX51	Channel 1±16 Low alarm flag bits
WX52	Channel 1±16 Overrange flag bits
WX53	Channel 1±16 Underrange flag bits
WX54	Channel 1±16 Arithmetic overflow flag bits
WX55	Channel 1±16 Open Thermocouple flag bits
WX56	Channel 1±16 Front panel temperature
.WX64	Reserved for future use

For each word, the bits are correlated to the channels according to the following:

MSB																		LSB
	1			0	0	0	0	0	0	0	0	0	0	0	0	0	0		16
																						CH 1



																		.
																		.
																		.
																						CH 16
																						CH 16

Figure 3-3 Input Flag Bits

If the peak or valley hold functions are enabled and Y31=1, then the data returned in WX49 ± WX64 is the peak (Y30=1) or valley (Y30=0) value measured. See Table 3-3.

Table 3-3 Peak/Valley Hold Input Words

WX 49

.

.

WX 64

Channel 1

.

.

Channel 16

Peak/Valley value

.

.

Peak/Valley value

3-6

Advanced Function Programming

SIMATIC 505±2557 Installation and Operation Guide

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Contents Simatic Copyright 1998 by Siemens Energy & Automation, Inc Manual Publication History List of Effective Pages Contents Iv Contents List of Figures List of Tables Preface Agency Approvals EuropeanCommunity CE ApprovalDescription 100 Ohm, 10 Ohm, 120 Ohm RTDs, or Millivolt InputsOperating Modes Word Input to the PLC from the Module RTD Input to Digital Conversion Scale UnitsSignals EffectOut-of-Range Input Effect of Voltage Input 10 Ohm Copper Resolution Input ResolutionInstalling and Configuring the Module Calculating the I/O Base Power BudgetSelecting 2 and 3 Wire or 4 Wire Operation Installing and Configuring the Module Configuring Temperature or SelectingMillivolt Input Selecting Degrees Celsius orFahrenheit Selecting DataConfiguration Jumper Locations Inserting Module IntoBase Wiring the Input Connectors Copper Wire Table at 25 Degrees CelsiusPress In Wiring Connector Wiring Diagram for 2, 3, or 4 Wire RTD Wiring Diagram for Millivolt Measurements Cable Grounding Example I/O Configuration Chart Advanced Function Programming Advanced Software Functions IntroductionOverview Advanced Setting the Module Configuration Jumper Logging Controller I/OMemory Internal Register Structures Input and Output Register OffsetsInput Registers Input Channel DataInput Flag Bits Peak/Valley Hold Input WordsOutput Data Registers AveragingFunction Enable Bits Control RegistersInputs Discrete Handshake Inputs Outputs Data Identification BitsLoading Data into the Simatic 505±2557 Module Data Loading ProcessSample Low and High Alarm Setpoints Identifying the Data Being Transferred 11 Enabling the Functions Loaded Loading Programs into the I/O Module 13 Startup Relay Ladder Logic Page When Using Timing Overhead for Functions EnabledTiming Considerations Timing ConstraintsDefault Values Default Function ValuesDefault Function Values for Simatic 505±2557 Additional Information about Each FunctionAlarm Setpoints DegreesCentigrade or Degrees FahrenheitDigital Filtering Averaging Peak and ValleyHold Hold Reset Flag BitsFunction PrecedenceTroubleshooting 10 Troubleshooting Flow Diagram Symptom Probable Cause Corrective ActionI/O Register Quick Reference 17 I/O Register Quick ReferenceOr K Memory Configuration Tables Page Addressing Worksheet Items Unique to the Simatic 505±2557 Module 18 Open RTD Status BitsTroubleshooting Specifications Table B-1 SpecificationsSpecifications subject to change without notice Jumper Settings Log Sheet Customer Response Business Reply Mail