Qualitrol 509ITM Series, Manual

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Heater Option
If the Enclosure or Panel Mount monitor is supplied with the Heater Option, the supply
power, 120 or 240 VAC, as specified when ordering, is applied to Terminal Block TB1
terminals 1 and 17, as shown in the Heater Option Connection figure.
Heater Option Connection
Qualitrol recommends that the heater circuit be installed with a fuse for safety and protection
purposes. The fuse is the responsibility of the installer. The rating of the heater is 120 VAC
and 100 W. A 240 VAC heater uses two of these heaters in a series, for a total of 200 W.
Qualitrol recommends installing an external slow-blow fuse rated at 1.25 or 1.5 A, at 600 V.
CAUTION:
Do not use DC voltage for powering the heater.
RTD Input Modules
Each RTD Input Module is specifically built to function with only a 10 ohm copper RTD or
only a 100 ohm Platinum RTD. For each RTD Input Module, one standard 10 ohm RTD or
100 ohm RTD, as specified, with a three-conductor, shielded cable is required to measure
liquid and ambient temperature, or if in a heated well, winding temperature. The three
conductors and the shield drain lead are connected to the monitor, as shown in the RTD
Input Wiring Connections figure.
CAUTION:
RTD wiring should be continuous, and the shield drain lead must be
grounded only at the instrument.
The monitor uses a compensation scheme for the RTD cable connection. The three-wire
connection compensates for the resistance of the connecting wires.