Manual

INSTALLATION AND OPERATING INSTRUCTIONS
SERIES 401 RTD TEMPERATURE TRANSMITTER
5211 Industrial Road • Fort Wayne, IN 46825 USA • [phone] FAX: [phone] • http://www.pyromation.com 3/02
 Copyright 2002 Pyromation, Inc. All rights reserved. Form 401f
Troubleshooting
Problem Possible Causes
No Current Flow in Signal Loop
• Current loop may be open at some point
• No Voltage out at power supply
• Reverse polarity on loop connection
Current Over 20 mA
• RTD is open
• Current loop connections shorted
Erratic Readings
• Loose connection in RTD or signal loop
• Damaged RTD
• AC noise on loop connections
• Exceeds loop resistance RL
Destructive Errors
• Do not connect power to the RTD input; this could destroy the unit
• Do not connect power to the RTD sensor
• Do not use AC line power
Non-Destructive Errors
• Reverse polarity on loop connection
• Do not connect multiple transmitter in series
Calibration
Pyromation RTD transmitters are factory calibrated. If recalibration is necessary, a zero and span adjustment can
be made from the top of the unit.
Note: adjustment to calibration will void warranty
1. Remove the RTD sensor wires and attach a RTD simulator.
2. Apply a simulated ‘zero’ resistance input and adjust the zero potentiometer for 4.00 mA output.
3. Apply a simulated ‘span’ resistance input and adjust the span potentiometer for 20.00 mA output.
4. The zero and span adjustments are interactive. Repeat steps 2 and 3 as necessary.
Application Hints
The calibrated output of the Pyromation transmitter is (4 to 20) mA. However, the lower and upper limits of output
current are approximately (2.2 and 30) mA respectively. This means that for a system using a 250 ohm resistor
( 1 to 5) V, the maximum voltage could be as high as 7.5 volts ( 30 mA x 250
Ω ) in the case of an open RTD.
Some computer based systems will not tolerate input voltages greater than approximately 5.5 volts. Instead of
selecting a different scaling resister (167
Ω for example gives 5 V for an open RTD), a 5.1 V zener diode in parallel
with the scaling resistor will clamp the voltage across the scaling resistor to 5.1 V while still allowing the calibrated
range to remain (1 to 5) V.
Limited Warranty
THE SERIES 401 RTD TEMPERATURE TRANSMITTER SOLD BY OR PURCHASED FROM PYROMATION, INC. OR FROM AN AUTHORIZED
PYROMATION, INC. DISTRIBUTOR, OR AGENT IS SUBJECT TO THE FOLLOWING LIMITED WARRANTY.
This product is warranted to be free from functional defects in materials and workmanship at the time the product leaves the Pyromation, Inc. factory, and to conform at that same time to the
specifications set forth in the relevant Pyromation, Inc. installation, wiring, operation manual for this product for a period of one year after shipment from the Pyromation, Inc. factory.
Pyromation’s exclusive and sole obligation, and Buyer’s exclusive and sole remedy under the above Limited Warranty is limited to either repair or replacement of such product, at
Pyromation’s option, free of charge to Buyer. Pyromation shall have no obligation to repair or replace unless the claimed defect in material or workmanship is reported in writing to
Pyromation at 5211 Industrial Road, Fort Wayne, Indiana 46825 within ten (10) days after delivery to the Buyer from Pyromation or an authorized Pyromation distributor, representative or
reseller. If so requested by Pyromation, the product shall be returned to a designated facility during normal business hours, transportation prepaid.
Any action for breach of this warranty or other action arising out of this contract must be commenced within one year after delivery.
Pyromation shall not be liable for any warranty, express or implied, other than the warranty stated above, and in the event of a breach of the above stated warranty, Pyromation shall not be
liable for any incidental, consequential, special, or other damages, costs, or expenses other than repair or replacement as described above. Pyromation excludes any and all warranties of
merchantability or fitness for a particular purpose. The above stated warranty extends only to the original Buyer from Pyromation, Inc. or from an authorized Pyromation distributor or agent,
and may not be transferred or assigned.