Omron E5AZ, Руководство пользователя

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Using HB and HS Alarms
Section 3-10
3-10 Using HB and HS Alarms
3-10-1 HB and HS Alarm Operations
• Heater burnout detection is executed by measuring heater current while
the control output for heating is ON, and HS detection is executed by
measuring heater current while it is OFF. For details, refer to the following
table.
(Heater burnout detection and HS detection cannot be used with the con-
trol output for cooling.)
Note (1) In the above diagram, power is considered to be ON (normal) if the heater
current is greater than the heater burnout detection current during the
Ton interval. If the heater is burned out, the measured current decreases
and falls below the heater burnout detection value. The output is then ac-
tivated as the heater burnout alarm.
(2) In the above diagram, power is considered to be OFF (normal) if the leak-
age current is less than the HS alarm current during the Toff interval. If
the SSR output is short-circuited, the measured current increases be-
yond the HS alarm value. The output is then activated as the HS alarm.
(3) Heater burnouts are not detected if the control output (heating) ON time
(Ton) is 190 ms or less.
(4) HS are not detected if the control output (heating) OFF time (Toff) is
190 ms or less.
• For models with HB and HS alarms, an OR output is established between
the ALM 1 function and the HB/HS alarm. If the ALM1 function is to be
used for HB and HS alarms only, set 0 as the ALM1 type and do not use
ALM1.
• Turn the heater power ON simultaneously or before turning ON the E5 @ Z
power. If the heater power is turned ON after turning ON the E5 @ Z power,
the HB alarm will be activated.
• Control is continued even when the HB or HS alarm is active.
• The rated current value may sometimes differ slightly from the actual cur-
rent flowing to the heater.
Use the “heater current 1 value monitor,” and “leakage current 1 monitor,”
parameters to check the actual current being used.
Heating control output status Power to heater HB alarm output HS alarm output
Control output
(heating)
Operation indicator
ON Lit Yes (Normal) (See note 1.) OFF ---
No (Heater burnout) ON ---
OFF Not lit Yes (HS alarm) --- ON
No (Normal) (See note 2.) --- OFF
Ton*3
ON
OFF
Toff*4
Control output (heating)