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M211920EN-C Quick Guide GMP251 and GMP252 Relay Box for GMP250 Carbon Dioxide Probes...
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This product contains software developed by The contents of this manual are subject to change Vaisala or third parties. Use of the software is without prior notice. governed by license terms and conditions Local rules and regulations may vary and they...
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This Quick Guide instructs how to carry out the serial line configuration and wiring related to using the current output for relay control. For more information on GMP251/252 serial line commands and other functionalities, see the user documentation of the probes: •...
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To enable relay operation, you must use a terminal program (for example, PuTTy) to set the GMP251/252 serial mode to relay communication and configure the relay settings. Using serial line (Vaisala Industrial Protocol) to configure the probe requires the following: •...
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Use the rsel command (not the asel command) to set the analog output channel to current (mA). 1. Connect GMP251/GMP252 to a computer with USB service cable 242659 and open a terminal connection (for example, PuTTy). 2. Enable advanced configuration commands with the pass 1300 command.
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• error_value = the current output when the probe is in error state The relay mode of GMP251 and GMP252 probes has been designed to use 12 mA as the relay control current. Use only 12 mA for the set_value configuration when using the relay box with GMP251 and GMP252.
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• error_value = the current output when the probe is in error state The relay mode of GMP251 and GMP252 probes has been designed to use 12 mA as the relay control current. Use only 12 mA for the set_value configuration when using the relay box with GMP251 and GMP252.
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Relay Box for GMP250 Carbon Dioxide Probes Quick Guide M211920EN-C 1.3.3 Serial Line Mode Commands Only serial mode commands related to relay operation are presented here. For other serial mode configuration options, see the User Guides of the GMP251/252 probes. Table 3 Smode Command Syntax Description smode<cr>...
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= Current (mA) output when the relay is activated. Set to 12 when using the relay box with GMP251/252. startup_value = During probe start-up, if the CO ppm level falls between the release_ppm and set_ppm values, startup_value shows the state of the relay (mA): the relay is either activated, released, or in error state.
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Relay Box for GMP250 Carbon Dioxide Probes Quick Guide M211920EN-C The relay mode of GMP251 and GMP252 probes has been designed to use 12 mA as the relay control current. Use only 12 mA for the set_value configuration when using the relay box with GMP251 and GMP252.
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Chapter 1 – Relay Box Quick Guide 1.5 Relay Box Dimensions The relay box dimensions are given in millimeters (mm). 40.6 Ø4...8 Figure 2 GMP250 Relay Box Dimensions...
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