Omron GRT1 - 11-2007 Operation Manual page 189

Temperature Input Units
Note
GRT1-TS2T
168
Item
Conversion cycle
Temperature conversion data Binary data two's complement (4-digit hexadecimal
Isolation method
Note For the GRT1-TS2P, a current of 0.35 mA flows to the platinum re-
sistance thermometer. For the GRT1-TS2PK, a current of
0.035 mA flows to the platinum resistance thermometer.
A 2-wire connection has a strong affect on the conductor resistance. When
using a 2-wire connection, the conductor resistance R directly determines the
error.
GRT1-TS2P: The error will be 4 ° C/ Ω for each line. For example, when using a
conductor with a resistance R of 1 Ω , the total conductor resistance would be
1 Ω × 2 = 2 Ω . Therefore, an error of 4 ° C/ Ω × 2 Ω = 8.0 ° C would occur.
GRT1-TS2PK: The error will be 0.4 ° C/ Ω for each line. For example, when
using a conductor with a resistance R of 1 Ω , the total conductor resistance
would be 1 Ω × 2 = 2 Ω . Therefore, an error of 0.4 ° C/ Ω × 2 Ω = 0.8 ° C would
occur.
R
A
R
B
Items
Model GRT1-TS2T
Input type Thermocouple
Number of 2 inputs (Two input words are allocated in the Master when normal
inputs display mode is selected or 4 words are allocated when 1/100 dis-
play mode is selected.)
Input type R, S, K, J, T, E, B, N, L, U, W, or PL2
Specifications
250 ms/2 points
when normal display mode is selected or 8-digit hexa-
decimal when 1/100 display mode is selected)
Between input and communications lines: Photocou-
pler isolation
Between temperature input signals: Photocoupler iso-
lation
Specifications
Section 6-4