Honeywell UDC2500 manual Input #1, Rtd

Installation

Input #1

Thermocouple	RTD	Millivolt or Volts
		except 0-10 Volts

Use Thermocouple extension wire only

25	R
3
26	+
27	–

25 R

26 + 27 –

25 R

mV or	+	26 +
Volt
source	–	27 –

0-10 Volts Milliamps Thermocouple Differential

0–10 Volt source

+

1

–

100K 1

2

100K 3

25 R

26 + 27 –

– 25 R

Xmitter		1
+				26	+
	250		Ω
	Power			27 –
	+ –
	Supply

Use Thermocouple
extension wire only		25	R
+
–	4	26	+
	2
–		27	–
+

1The 250 ohm resistor for milliamp inputs or the voltage divider for 0-10 Volt inputs are supplied with the controller when those inputs are specified. These items must be installed prior to start up when the controller is wired. For 0-20 mA applications, the resistor should be located at the transmitter terminals if Burnout detection is desired.

2Splice and tape this junction between the two thermocouples. This junction may be located anywhere between the thermocouples and the instrument terminals, it does not need to be close to the other thermocouple junctions. Both thermocouples must be of the same type. For best accuracy, the two thermocouples should be matched or, preferably, made from the same batch of wire.

3This controller does not produce a steady current for burnout detection. For that reason, when a thermocouple is used in parallel with another instrument, it may be desirable to configure the burnout selection for this controller to “NOFS” and use the burnout current from the other instrument to also drive this controller.

4The millivolt values for the Thermocouple Differential Input are for a pair of J thermocouples at an ambient temperature mean of 450°F / 232°C.

Figure 2-6 Input 1 Connections

4/07 UDC2500 Universal Digital Controller Product Manual 23