Tempco TEC-2500, Инструкция по эксплуатации, Страница: 62 / 108

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3–25 Heater Current Monitoring
TEC99999, a current transformer, can be equipped to measure the heater
current. Select CT for IN2. The input 2 signal conditioner measures the heater
current while the heater is powered and the current value will remain
unchanged while the heater is unpowered. The PV2 will indicate the heater
current. For information on how to read PV2 value, please refer to section 3-24.
Alarms and other actions can then be set using heater current as a process
value
NOTES
If the heater to be measured is controlled by output 1, then CYC1 should be set
for 1 second or longer and O1TY should use RELY, SSRD, or SSR. Similarly, if
the heater to be measured is controlled by output 2, then CYC2 should be set
for 1 second or longer and O2TY should use RELY, SSRD, or SSR to provide
an adequate time for the A to D converter to measure the signal.
Since TEC99999 can detect a full-wave AC current only, a DC or half-wave AC
current can't be measured.
3–26 Reload Default Values
The default values listed in table 1.4 are stored in the memory when the
product leaves the factory. On certain occasions, it is desirable to retain these
values after the parameter values have been changed. Here is a convenient
way to reload the default values.
Operation
Press several times until appears. Then press . The upper
display will show .Use the up and down keys to select 0 or 1. If °C units
are required, select 0 for FILE and if °F units are required, select 1 for FILE.
Then press for at least 3 seconds. The display will flash for a moment while
the default values are reloaded.
CAUTION
The procedure mentioned above will change the previous setup data. Before
performing it, make sure that it is really required.
Accessory installed:
TEC99999
Setup
IN2=CT
O1TY or O2TY=RELY, SSRD or SSR
CYC1 or CYC2
≥
1 second
Limitations
1. Linear output type can't be used.
2. CYC1 (or CYC2) should be set for
1 second or longer to detect heater
current reliably.
3. Only full-wave AC current can be
detected.
FILE 0
°C default file
FILE 1
°F default file