12 96VTR Ver. 2.0 11/99
Timer (selection 8) in parameter "A1Fu". Set the time to 120 minutes (2 hours) in
parameter "timE". When the controller is powered the alarm relay will be OFF, when
the PV = SV the relay remains OFF but the timer begins to countdown, and after 2
hours the relay will turn ON permitting the process event to take place.
12. RS-485 OPTION
The optional RS-485 PC interface permits up to 32 controllers to be connected to a PC for
remote operation. Each controller must have a unique address between 0 and 31 which is
programmed in parameter "addr". The "remo" parameter must be set to '1' to activate a
controller’s interface. The RS-485 wiring terminals are shown in Figure 3, Section 4.
Detailed information is provided with the purchase of the RS-485 option.
13. CUSTOMER SERVICE
Extech offers complete repair and calibration services
for all of the products we sell.
For periodic calibration, NIST certification or repair of any Extech product, call customer
service for details on services available. Extech recommends that calibration be performed
on an annual basis to insure calibration integrity.
14. WARRANTY
EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects
in parts and workmanship for one year from date of shipment (a limited warranty may
apply on sensors and cables). If it should become necessary to return the instrument for
service during or beyond the warranty period, contact the Customer Service Department
at (781) 890-7440 for authorization.
A Return Authorization (RA) number must be
issued before any product is returned to Extech.
The sender is responsible for
shipping charges, freight, insurance and proper packaging to prevent damage in transit.
This warranty does not apply to defects resulting from action of the user such as misuse,
improper wiring, operation outside of specification, improper maintenance or repair, or
unauthorized modification. Extech specifically disclaims any implied warranties or
merchantability or fitness for a specific purpose and will not be liable for any direct,
indirect, incidental or consequential damages. Extech's total liability is limited to repair or
replacement of the product. The warranty set forth above is inclusive and no other
warranty, whether written or oral, is expressed or implied.
Copyright
©
1999 Extech Instruments Corporation. All rights reserved
including the right of reproduction in whole or in part in any form.
APPENDICES
Appendix A: Alarm Mode Selections for parameters 'A1Fu' and 'A2Fu"
'00' Deviation High Alarm
: For the Deviation High Alarm, the value entered for the
"A1SP" (Alarm 1 setpoint) or 'A2SP" (Alarm 2 setpoint) parameters equals the
amount the controller's HIGH alarm setpoint is offset from the main controller
setpoint. For example, if SV = 400 and A1SP = +10 then the Limit Alarm relay will
trip when the temperature reaches 410
o
. The Deviation alarm setpoint tracks the
main setpoint meaning that it changes as the main setpoint changes always
remaining a programmed number of units from the main setpoint.
'01' Deviation Low Alarm:
With the Alarm setup as a Deviation Low Alarm, the value
entered for the "A1SP" (Alarm 1 setpoint) or 'A2SP" (Alarm 2 setpoint) parameters
equals the amount to which the controller's LOW alarm setpoint is offset from the
main controller setpoint. For example, if you entered SV = 400 and A1SP = -10
then the Alarm relay will trip when the temperature falls below 390
o
. The Deviation
alarm setpoint tracks the main setpoint meaning that it changes as the main
