T7750A-D Wall Modules. CSI 3-Part Specifications. Large file (>500kB).

T7750A,B,C,D Wall Modules

 

FEATURES

• Integral 20K ohm thermistor is linearized in the models used with Excel 10 Controllers.
• T7750A1018 model is field modifiable for use with Excel 10 Controllers or Excel 600, 500, 100, 80, and 20 Controllers.
• T7750B2006 and T7750B2014 Models use a 20K ohm non-linearized thermistor and a 10K ohm setpoint adjustment that are used only with Excel 600, 500, 100, 80, and 20 Controllers.
• Operating range of 55 to 85°F (13 to 29.5°C).
• T7750C and T7750D Models with occupied/unoccupied override are available for use only with Excel 10 Controllers.
• Designed for a vertical mounting.

GENERAL

The T7750A,B,C,D are direct-wired wall modules used with an Excel 10 Controller. The T7750A1018 is a field-modifiable wall module for use with Excel 10 Controllers or Excel 600, 500, 100, 80, and 20 Controllers. The T7750B2006 and the T7750B2014 models are used only with Excel 600, 500, 100, 80, and 20 Controllers. The zone being controlled uses a wall module as a sensor input for ambient temperature sensing in a minimum system configuration. The T7750 Wall Modules provide the following additional combination of options to the customer: analog setpoint input and for models used with Excel 10 Controllers, override (bypass) digital input contact, LED status indicator and network access jack.

SPECIFICATIONS

The T7750A,B,C,D have two-piece construction, a cover and an internally wired subbase. Field wiring 14 to 22 AWG (2.0 to 0.325 mm 2 ) for models T7750A,B,C,D is connected to a terminal block in the subbase. The wall module can then be activated by simply plugging it into the pre-wired subbase. See Table 1 for features available with each T7750A,B,C,D model.

 

 

Models used with Excel 10 Controllers

Temperature Sensor Accuracy

The transmitted temperature contained within the network must indicate the temperatures in Table 2 when each of the resistances, as measured across terminals T3 and T4 of the wall module, is applied to the Excel 10 Controller sensor input terminals.

Communications:

The T7750 uses a transformer-coupled communications port with encoded data presented to controllers and devices on the E-Bus at 78K bits per second. Using the transformer-coupled communications interface offers a much higher degree of common mode noise rejection while assuring dc isolation. The E-Bus is insensitive to polarity, eliminating miswiring errors during installation.

The recommended wire size used for the E-Bus is Level IV 22 AWG (0.325 mm 2 ) or plenum rated Level IV 22 AWG (0.325 mm 2 ) nonshielded, twisted pair, solid conductor wire.

 

Status Information

T7750C,D Wall Module Override LEDs

The remote override LED, located on either the T7750C or T7750D Wall Module in Fig. 2, displays the manual override mode of the controller. The status information is described Table 3.

 

1. LED = Off. No override active.

2. LED = Continuously on. Bypass mode, timed occupied override.

3. LED = One flash per second. Continuous unoccupied override.

4. LED = Two flashes per second. Remote only, continuous occupied override.

 

T7750C,D Wall Module Bypass Pushbutton

The wall module bypass pushbutton, located on either the T7750C or T7750D Wall Module in Fig. 2, can change the controller into the first three wall module bypass modes listed in the Wall Module Status column in Table 3.

T7750B2006/T7750B2014 Models used with Excel 600, 500, 100, 80, and 20 Controllers

Temperature Sensor Accuracy

The temperature sensor element for these models is a standard non-linearized 20K ohm Negative Temperature Coefficient (NTC) sensor. The sensor characteristics, as measured across terminals T3 and T4 of the wall module, are applied to the Excel 600, 500, 100, 80, and 20 Controller sensor input terminals. See Table 4.

 

Setpoint Accuracy

Wall module setpoint adjustments are made using its 10K ohm potentiometer. Reading the setpoint with an Excel 600, 500, 100, 80, and 20 Controller requires that the data point in CARE must be configured with a custom I/O characteristic. Tables 5 and 6 indicate the setpoint accuracy as measured across terminals T3 and T5 of the wall module. Table 7 contains the values for the custom setpoint I/O characteristic that must be entered in CARE.

 

 

Mounting Options

The T7750 can be mounted on a standard 2 x 4 in. junction box or on a 60 mm diameter junction box. The subbase provides the slotted hole pattern for the T7412 Wall series IRC devices.

Dimensions:

5-1/32(h) x 3-5/32(w) x 1-19/32(d) in.

(128(h) x 80(w) x 41(d) mm).

Environmental Ratings:
Operating Temperature
45° to 99°F (7.2° to 37.2°C).

Shipping Temperature
-40° to 150°F (-40° to 65°C).

Relative Humidity
5% to 95% noncondensing.