Model TT231-0600
Two-Wire RTD Transmitter w/USB
Acromag, Inc. Tel: 248-295-0880
- 24 - http://www.acromag.com
- 24 -
http://www.acromag.com
Break Detection
Select Upscale or Downscale Lead Break Detection…
Upon sensor burnout or a broken sensor lead, you can select
“Downscale
” to send
the output current to the under-scale alarm limit, which is ~0.4mA less than the
under-scale threshold. Otherwise, you can select
“Upscale”
to send the output to
the over-scale alarm limit, which is ~1mA above the over-scale threshold. By using
alarm levels outside of a defined linear operating range, a lead break or open sensor
can be easily discerned from an over-range or under-range input signal by noting its
current level.
Read Status
(Optional) Read Status & Reset Unit…
You can use the
“Read Status”
button to display fault status information relative to
the input signal. The fault status error level will be indicated in the “Fault Status:”
message field, and any additional diagnostic information will be displayed in the
message window at the bottom of the screen. Possible fault status levels and
diagnostic messages are indicated below:
FLT LEVEL
FAULT INDICATION
0 or None
Normal Operation, No Faults
1*
IN- Exceeds Positive Limit
2*
IN- Exceeds Negative Limit
3
IN+ Exceeds Positive Limit
4
IN+ Exceeds Negative Limit
5
IN+ Exceeds Positive Limit & IN- Exceeds Positive Limit
6
IN+ Exceeds Positive Limit & IN- Exceeds Negative Limit
7
IN+ Exceeds Negative Limit & IN- Exceeds Positive Limit
8
IN+ Exceeds Negative Limit & IN- Exceeds Negative Limit
ELSE
“Error Reading Unit. Check Connections and try again.”
*Note:
A two-wire sensor cannot correctly register IN- errors, as this always
requires a third sensor lead. A break at IN- will return Fault Level 3, the same as a
break at IN+. If an IN- error is flagged with a 2-wire sensor, it refers to the short
jumper wire placed between terminals 3 & 4 of the unit, which supplants the third
sensor lead for 2-wire input connections. Failure to install this jumper for 2-wire
sensors will drive error level 5 (see below).
Normally, after clicking “Read Status”, No Faults will be indicated and “Read
Complete! Normal Operation, inputs in range” will be displayed in the message bar.
For a 3-wire sensor, a break in the IN+ lead will return “Fault Code:3 (Positive Input
Exceeds Positive Limit)”. A break in the IN- lead will return “Fault Code: 1 (Negative
Input exceeds Positive Limit)”. A break in the third lead that connects to terminal 4
will return “Fault Code: 5 (Positive Input exceeds positive Limit and Negative Input
exceeds Positive Limit)”.